Pelvic discontinuity is a separation through the acetabulum with the ilium displacing superiorly and the ischium/pubis displacing inferiorly. This is a biomechanically challenging environment with a high rate of failure for standard acetabular components. The cup-cage reconstruction involves the use of a highly porous metal cup to achieve biological bone ingrowth on both sides of the pelvic discontinuity and an ilioischial cage to provide secure fixation across the discontinuity and bring the articulating hip center to the correct level. The purpose of this study was to report long term follow up of the use of the cup-cage to treat pelvic discontinuity.

All hip revision procedures between January 2003 and January 2022 where a cup-cage was used for a hip with a pelvic discontinuity were included in this retrospective review. All patients received a Trabecular Metal Revision Shell with either a ZCA cage or TMARS cage (Zimmer-Biomet Inc.). Pelvic discontinuity was diagnosed on pre-operative radiographs and/or intraoperatively. Kaplan-Meier survival analysis was performed with failure defined as revision of the cup-cage reconstruction.

Fifty-seven cup-cages in 56 patients were included with an average follow-up of 6.25 years (0.10 to 19.98 years). The average age of patients was 72.09 years (43 to 92 years) and 70.2% of patients were female. The five year Kaplan-Meier survival was 92.0% (95% CI 84.55 to 99.45) and the ten year survival was 80.5% (95% CI 58.35 to 102.65). There were 5 major complications that required revision of the cup-cage reconstruction (3 infections and 2 mechanical failures). There were 9 complications that required re-operation without revision of the cup-cage reconstruction (5 dislocations, 3 washouts for infection and one femoral revision for aseptic loosening).

In our hands the cup-cage reconstruction has provided a reliable tool to address pelvic discontinuity with an acceptable complication rate.

Inaccurate component placement during total hip arthroplasty (THA) can have significant and costly consequences. Malpositioning of the acetabular cup components can lead to dislocation and revision surgery, while postoperative discrepancies in leg length can lead to biomechanical imbalances, causing chronic low back pain. Current methods for monitoring these parameters intraoperatively rely on manual methods such as tissue tensioning or on the surgeon's experience, both of which are subject to inaccuracies. Computer-assisted navigation, while currently used in only a small percentage of THA procedures, is an emerging technology that has the potential to improve the accuracy with which surgeons place components during THA by providing real-time, intraoperative data. One innovative navigation system – Intellijoint HIP^® (Intellijoint Surgical, Waterloo, ON) – has demonstrated its accuracy, time-neutrality, safety and effectiveness in clinical studies and has the potential to improve outcomes and reduce re-admissions and revisions during both primary and revision THA.

The ability to assist with placement of the cup component at a preoperative target is a hallmark of navigation systems. In studies examining the proportion of cups placed within Lewinnek's safe zone, significantly more cups were placed within this zone with the Intellijoint system than when using traditional methods (anteversion: 58% vs. 37%, p=0.005; inclination: 87% vs. 67%, p=0.002). Similarly, surgeons were better able to place the cup at a functional orientation of 40 degrees inclination/20 degrees anteversion, with a significantly higher proportion of cups placed within 10 degrees of this target while using the Intellijoint system (70%) than during conventional THA (53%, p=0.02).

In comparisons with postoperative imaging, the Intellijoint system has demonstrated excellent accuracy. In a recent study, intraoperative measurements of anteversion and inclination were within 3.3 ± 3.1 degrees and 1.1 ± 0.9 degrees, respectively, of postoperative 3D EOS imaging. Results for leg length discrepancy are similarly accurate: across several studies, the mean difference between navigation and radiographic measurements ranged from 0.3 to 4.3mm. Evidence indicates that the 90-day rates of dislocation and revision surgery following primary THA with the Intellijoint system were substantially lower than rates associated with traditional methods. These results hold true following navigation-assisted revision surgery as well. At 90 days, 1 year and 2 years post-procedure, no dislocations were reported.

Beyond dislocation, the overall rate of adverse events in cases using Intellijoint has been reported as remarkably low. No device-related fractures have been reported, nor have any instances of postoperative pain at the sites of the surgical pins supporting the camera and/or tracker components. Finally, there is no significant increase in surgical time associated with the use of this device, with a large study comparing navigated THA with traditional THA showing a 2.9-minute increase in procedural time (p=0.60), 1.0 minute of which occurs prior to primary incision (unpublished data).

Computer-assisted navigation – and the Intellijoint HIP system specifically – has demonstrated the ability to improve the accuracy with which surgeons implant components during THA without adversely affecting operating room efficiency or patient safety. This technology has the potential to dramatically improve patient-related outcomes in both the short- and long-term and represents the benefits associated with advanced technologies in the operating room.

Important issues related to total hip replacement for dysplasia are: placement of the cup and bone stock, the role of femoral osteotomy, and the choice of acetabular and femoral components.

The cup can be placed at the correct or near correct anatomical level with or without a bone graft, in a high position (high hip center) or at the right level in a protruded position. All three techniques can provide adequate coverage of the cup. In the high hip position bone graft is not usually necessary to obtain cup coverage. There is, however, a higher rate of component loosening, a higher dislocation rate, and lengthening is limited to the femoral side. Placing the cup in a protruded position to obtain coverage does not restore bone stock for future surgery, but it does place the hip at the correct level. Placing the cup in the correct anatomical position (i.e. at the right level and not protruded) may require a structural autograft which adds to the complexity of the case. However, bone stock is restored for future surgery. Revision of acetabular components that have had a shelf graft have a survivorship of 96.5% at 10 years and only 5 of 34 required structural support (2 augments, 3 structural allografts).

Femoral osteotomy may be used as part of the exposure for diaphyseal shortening or for derotation of excessive anteversion. The osteotomy is carried out in the sub-trochanteric region and may be oblique, step-cut or transverse. Fixation of the osteotomy is achieved via the stem, a plate, or a cortical strut.

Cementless components are usually used because of the relatively young age of this patient population. Small components may be necessary. On the femoral side, the stem should be straight or modular so excessive anteversion can be neutralised.

An expert panel of orthopaedic surgeons is going to be evaluating primary and revision total hip and total knee replacements submitted by the audience. Participants will present the x-rays and clinical findings of difficult cases for which they are seeking an expert opinion from the panel. The panel will probably have conflicting opinions which will lead to an entertaining and educational session. The moderator will also provide some extremely challenging cases once again, to stimulate more controversy. This session has been very popular in the past and is fast moving, humorous and educational.

An osteochondral defect greater than 3cm in diameter and 1cm in depth is best managed by an osteochondral allograft.

If there is an associated knee deformity, then an osteotomy is performed. In our series of osteochondral allografts for large post-traumatic knee defects realignment osteotomy is performed about 60% of the time in order to off-load the transplant. To correct varus we realign the proximal tibia with an opening wedge osteotomy. To correct valgus, we realign the distal femur with a closing wedge osteotomy.

Our results with osteochondral allografts for the large osteochondral defects of the knee both femur and tibia, have been excellent in 85% of patients at an average follow-up of 10 years. The Kaplan-Meier survivorship at 15 years is 72%. At an average follow-up of 22 years in 58 patients with distal femoral osteochondral allograft, 13 have been revised (22%). The 15-year survivorship was 84%.

Retrieval studies of 24 fresh osteochondral grafts obtained at graft revision or conversion total knee replacement at an average of 12 years (5 – 25) revealed the following. In the areas where the graft was still intact, the cartilage was of normal thickness and architecture. Matrix staining was normal except in the superficial and upper mid zones. Chondrocytes were mostly viable but there was chondrocyte clusters and loss of chondrocyte polarity. Host bone had extended to the calcified cartilage but variable remnants of dead bone surrounded by live bone persisted. With a stable osseous base the hyaline cartilage portion of the graft can survive for up to 25 years.

An osteochondral defect greater than 3cm in diameter and 1cm in depth is best managed by an osteochondral allograft.

If there is an associated knee deformity, then an osteotomy was performed. In our series of osteochondral allografts for large post-traumatic knee defects, realignment osteotomy is performed about 60% of the time in order to off load the transplant. To correct varus we realign the proximal tibia with an opening wedge osteotomy. To correct valgus, we realign the distal femur with a closing wedge osteotomy.

Our results with osteochondral allografts for the large osteochondral defects of the knee both femur and tibia, have been excellent in 85% of patients at an average follow-up of 10 years. The Kaplan-Meier survivorship at 15 years is 72%. At an average follow-up of 22 years in 58 patients with distal femoral osteochondral allograft, 13 have been revised (22%). The 15-year survivorship was 84%.

Retrieval studies of 24 fresh osteochondral grafts obtained at graft revision or conversion to total knee replacement at an average of 12 years (5 – 25) revealed the following. In the areas where the graft was still intact, the cartilage was of normal thickness and architecture. Matrix staining was normal except in the superficial and upper mid-zones. Chondrocytes were mostly viable but there was chondrocyte clusters and loss of chondrocyte polarity. Host bone had extended to the calcified cartilage but variable remnants of dead bone surrounded by live bone persisted. With a stable osseous base the hyaline cartilage portion of the graft can survive for up to 25 years.

In our center the cup cage reconstruction is our most common technique where a cage is used, especially if there is a pelvic discontinuity.

Cup Cage Construct – in this construct there must be enough bleeding host bone to stabilise the ultraporous cup which functions like a structural allograft supporting and eventually taking the stress off the cage. This construct is ideal for pelvic discontinuity with the ultraporous cup, i.e., bridging and to some degree distracting the discontinuity. If, however, the ultra-porous cup cannot be stabilised against some bleeding host bone, then a conventional stand-alone cage must be used.

Acetabular bone loss and presence of pelvic discontinuity were assessed according to the Gross classification. Sixty-seven cup cage procedures with an average follow-up of 74 months (range, 24–135 months; SD, 34.3 months) were identified; 26 of 67 (39%) were Gross Type IV and 41 of 67 (61%) were Gross Type V (pelvic discontinuity). Failure was defined as revision surgery for any cause, including infection.

The 5-year Kaplan-Meier survival rate with revision for any cause representing failure was 93% (95% confidence interval, 83.1–97.4), and the 10-year survival rate was 85% (95% CI, 67.2–93.8). The Merle d'Aubigné-Postel score improved significantly from a mean of 6 pre-operatively to 13 post-operatively (p < 0.001). Four cup-cage constructs had non-progressive radiological migration of the ischial flange and they remain stable.

Important issues related to total hip replacement for dysplasia are: placement of the cup and bone stock; the role of femoral osteotomy, and the choice of acetabular and femoral components.

The cup can be placed at the correct or near correct anatomical level with or without a bone graft, in a high position (high hip center) or at the right level in a protruded position. All three techniques can provide adequate coverage of the cup. In the high hip position bone graft is not usually necessary to obtain cup coverage. There is, however, a higher rate of component loosening, a higher dislocation rate, and lengthening is limited to the femoral side. Placing the cup in a protruded position to obtain coverage does not restore bone stock for future surgery, but it does place the hip at the correct level. Placing the cup in the correct anatomical position (i.e., at the right level and not protruded) may require a structural autograft which adds to the complexity of the case. However, bone stock is restored for future surgery.

Femoral osteotomy may be used as part of the exposure for diaphyseal shortening or for derotation of excessive anteversion. The osteotomy is carried out in the sub-trochanteric region and may be oblique, step-cut or transverse. Fixation of the osteotomy is achieved via the stem, a plate, or a cortical strut.

Cementless components are usually used because of the relatively young age of this patient population. Small components may be necessary. On the femoral side, the stem should be straight or modular so excessive anteversion can be neutralised.

An expert panel of orthopaedic surgeons is going to be evaluating primary and revision total hip and total knee replacements submitted by the audience. Participants will present the x-rays and clinical findings of difficult cases for which they are seeking an expert opinion from the panel. The panel will probably have conflicting opinions which will lead to an entertaining and educational session. The moderator will also provide some extremely challenging cases to stimulate more controversy. This session has been very popular in the past and is fast moving, humorous and educational.

The indications for cementless acetabular fixation have been broadened because our data supports the use of trabecular metal cups even when there's limited bleeding host bone contact. Trabecular metal augments have allowed us to use cementless cups when there is segmental loss of bone.

Surgical Technique: The acetabular bed is prepared. If there is less medial bone stock than 2mm, then morselised allograft is impacted by reverse reaming. When reaming is complete and less than 50% bleeding host bone is available for cup stabilisation, then a trabecular metal cup is indicated.

Trabecular augments are used if the trabecular cup trial is not stable, or if it is uncovered by 40% or more. The conventional augments come in different sizes to accommodate the diameter of the cup and the size of the defect. Larger defects are addressed with anterior and posterior column augments, and superior defects with figure of seven augments. Augments are fixed with at least two screws. The interface between the cup and the augments should be stable, but some surgeons place a very thin layer of cement between the augment and cup so micromotion does not occur while ingrowth is occurring.

We have used trabecular metal augments in 46 acetabular revisions in conjunction with a trabecular metal cup. Thirty-four cases have at least 2 years follow-up with an average of 64.5 months. There have been 4 cup loosenings with 3 re-revisions.

An expert panel of orthopaedic surgeons is going to be evaluating primary and revision total hip and total knee replacements submitted by the audience. Participants will present the x-rays and clinical findings of difficult cases for which they are seeking an expert opinion from the panel. The panel will probably have conflicting opinions which will lead to an entertaining and educational session. The moderator will also provide some extremely challenging cases once again, to stimulate more controversy. This session has been very popular in the past and is fast moving, humorous and educational.

Acetabular cages are necessary when an uncemented or cemented cup cannot be stabilised at the correct anatomic level. Impaction grafting with mesh for containment of bone graft is an alternative for some cases in centers that specialise in this technique.

At our center we use three types of cage constructs –

(A)

Conventional cage ± structural or morselised bone grafting. This construct is used where there is no significant bleeding host bone. This construct is susceptible to cage fatigue and fracture, This reconstruction is used in young patients where restoration of bone stock is important.

In our center the cup-cage reconstruction is our most common technique where a cage is used, especially if there is a pelvic discontinuity.

Acetabular bone loss and presence of pelvic discontinuity were assessed according to the Gross classification. Sixty-seven cup-cage procedures with an average follow-up of 74 months (range, 24–135 months; SD, 34.3) months were identified; 26 of 67 (39%) were Gross Type IV and 41 of 67 (61%) were Gross Type V (pelvic discontinuity). Failure was defined as revision surgery for any cause, including infection.

The 5-year Kaplan-Meier survival rate with revision for any cause representing failure was 93% (95% confidence interval, 83.1–97.4), and the 10-year survival rate was 85% (95% CI, 67.2–93.8). The Merle d'Aubigné-Postel score improved significantly from a mean of 6 pre-operatively to 13 post-operatively (p < 0.001). Four cup-cage constructs had non-progressive radiological migration of the ischial flange and they remain stable.

An expert panel of orthopaedic surgeons is going to be evaluating primary and revision total hip and total knee replacements submitted by the audience. Participants will present the x-rays and clinical findings of difficult cases for which they are seeking an expert opinion from the panel. The panel will probably have conflicting opinions which will lead to an entertaining and educational session. The moderator will also provide some extremely challenging cases once again, to stimulate more controversy. This session has been very popular in the past and is fast moving, humorous and educational.

The indications for cementless acetabular fixation have been broadened because our data supports the use of trabecular metal cups even when there's limited bleeding host bone contact. Trabecular metal augments have allowed us to use cementless cups when there is segmental loss of bone.

Surgical Technique: The acetabular bed is prepared. If there is less medial bone stock than 2 mm, then morselised allograft is impacted by reverse reaming. When reaming is complete and less than 50% bleeding host bone is available for cup stabilization, then a trabecular metal cup is indicated.

Trabecular augments are used if the trabecular cup trial is not stable, or if it is uncovered by 40% or more. The conventional augments come in different sizes to accommodate the diameter of the cup and the size of the defect. Larger defects are addressed with anterior and posterior column augments, and superior defects with figure of seven augments. Augments are fixed with at least two screws. The interface between the cup and the augments should be stable, but some surgeons place a very thin layer of cement between the augment and cup so micromotion does not occur while ingrowth is occurring.

We have used trabecular metal augments in 46 acetabular revisions in conjunction with a trabecular metal cup. Thirty-four cases have at least 2 years follow-up with an average of 64.5 months. There has been 4 cup loosenings with 3 re-revisions. Our most up to date data is 101 cases with an average follow-up of 3 years. There has been one infection that underwent a two stage revision. There are 4 loose cups – 3 revised.

The parameters to be considered in the selection of a cartilage repair strategy are: the diameter of the chondral defect; the depth of the bone defect; the location of the defect (weight bearing); alignment.

A chondral defect less than 3 cm in diameter can be managed by surface treatment such as microfracture, autologous chondrocyte transplantation, mosaicplasty, or periosteal grafting.

An osteochondral defect less than 3 cm in diameter and less than 1 cm in depth can be managed by autologous chondrocyte transplantation, mosaicplasty or periosteal grafting.

An osteochondral defect greater than 3 cm in diameter and 1 cm in depth is best managed by an osteochondral allograft.

If there is an associated knee deformity, then an osteotomy should also be performed with all of the aforementioned procedures. In our series of osteochondral allografts for large post-traumatic knee defects realignment osteotomy is performed about 60% of the time in order to off load the transplant. To correct varus we realign the proximal tibia with an opening wedge osteotomy. To correct valgus, we realign the distal femur with a closing wedge osteotomy.

Our results with osteochondral allografts for the large osteochondral defects of the knee have been excellent in 85% of patients at an average follow-up of 10 years. The Kaplan-Meier survivorship at 15 years is 72%. At an average follow-up of 22 years in 58 patients with distal femoral osteochondral allograft, 13 have been revised (22%). The 15-year survivorship was 84%.

The results for the hip are early. To date we have performed this procedure on 16 patients. Surgical dislocation of the hip is carried out via a trochanteric osteotomy and the defect defined and trephined out. A press-fit fresh osteochondral allograft is inserted using the trephine technique. We have published our early results on a series of 8 patients with 5 good to excellent results, 1 fair result and 2 failures.

Total hip arthroplasty (THA) represents one of the most safe and effective medical procedures. However, with an unchanged rate of 3% in primary and 10% in revision THAs, despite alleged surgical technique and implant design improvements, dislocation continues to be a matter of concerns with important functional and financial consequences. A number of parameters influence the risk for dislocation including patient specific factors, surgeon experience, femoral head size, implant orientation, and surgical approach. The latter has been less investigated during the past 15 years, as it was supposed that large femoral heads or specifically designed implants such as dual mobility sockets would notably decrease the risk for dislocation. Also, minimally invasive approach including the anterior approach, and rapid recovery have been aggressively marketed, making the transtrochanteric approach rarely if ever used by most surgeons. Also, this surgical technique is demanding and time consuming, not exactly what is expected in the 21st century. However, there are some clear advantages to the transtrochanteric approach both in primary and revision THAs: it gives a large view on the acetabulum allowing for anatomic reconstruction of the artificial joint and correct implants orientation; it allows for preservation of the entire periarticular muscles and tendons including the external rotators (external obturator+++); and it permits to balance the abductors tension by lowering and/or translating the greater trochanter. These advantages can notably reduce the rate of dislocation in both primary and revision THAs. Data from our institution including senior and junior surgeons have showed rates of dislocation ranging from 0.1 to 1.7% in primary THAs and from 1.5 to 2.3% in revision THAs. Our rate of nonunion is less than 2% even in revision using a specifically designed trochanteric claw plate almost systematically used in revision THAs to allow for a more rigid fixation. Finally, the transtrochanteric approach can be extended to the femur to cope with specific situations. The surgical tips and tricks of this approach will be discussed in the presentation.

Acetabular cages are necessary when an uncemented or cemented cup cannot be stabilised at the correct anatomic level. Impaction grafting with mesh for containment of bone graft is an alternative for some cases in centers that specialise in this technique.

At our center we use three types of cage constructs –

(A) Conventional cage ± structural or morselised bone grafting. This construct is used where there is no significant bleeding host bone. This construct is susceptible to cage fatigue and fracture. This reconstruction is used in young patients where restoration of bone stock is important.

(B) Conventional cage in combination with a porous augment where contact with bleeding host bone can be with the ilium and then by the use of cement that construct can be unified. The augment provides contact with bleeding host bone and if and when ingrowth occurs, the stress is taken off the cage.

(C) Cup Cage Construct – in this construct there must be enough bleeding host bone to stabilise the ultra-porous cup which functions like a structural allograft supporting and eventually taking the stress off the cage. This construct is ideal for pelvic discontinuity with the ultra-porous cup, i.e., bridging and to some degree distracting the discontinuity. If, however, the ultra-porous cup cannot be stabilised against some bleeding host bone, then a conventional stand-alone cage must be used.

In our center the cup cage reconstruction is our most common technique where a cage is used, especially if there is a pelvic discontinuity.

Acetabular bone loss and presence of pelvic discontinuity were assessed according to the Gross classification. Sixty-seven cup-cage procedures with an average follow-up of 74 months (range, 24–135 months; SD, 34.3) months were identified; 26 of 67 (39%) were Gross Type IV and 41 of 67 (61%) were Gross Type V (pelvic discontinuity). Failure was defined as revision surgery for any cause, including infection.

The 5-year Kaplan-Meier survival rate with revision for any cause representing failure was 93% (95% confidence interval, 83.1–97.4), and the 10-year survival rate was 85% (95% CI, 67.2–93.8). The Merle d'Aubigné-Postel score improved significantly from a mean of 6 pre-operatively to 13 post-operatively (p < 0.001). Four cup-cage constructs had non-progressive radiological migration of the ischial flange and they remain stable.

Acetabular cages are necessary when an uncemented or cemented cup cannot be stabilised at the correct anatomic level. Impaction grafting with mesh for containment of bone graft is an alternative for some cases in centers that specialise in this technique.

At our center we use three types of cage constructs:

(A)

Conventional cage ± structural or morselised bone grafting. This construct is used where there is no significant bleeding host bone. This construct is susceptible to cage fatigue and fracture. This reconstruction is used in young patients where restoration of bone stock is important.

In our center the cup cage reconstruction is our most common technique where a cage is used, especially if there is a pelvic discontinuity.

Patients with longstanding hip fusion are predisposed to symptomatic degenerative changes of the lumbar spine, ipsilateral knee and contralateral hip. In such patients, conversion of hip arthrodesis to hip replacement can provide relief of such symptoms. However, this is a technically demanding procedure associated with higher complication and failure rates than routine total hip replacement.

The aim of this study was to determine the early functional results and complications in patients undergoing hip fusion conversion to total hip replacement, performed or supervised by a single surgeon, using a standardised approach and uncemented implants. We hypothesised that a satisfactory functional improvement can be achieved in following conversion of hip fusion to hip replacement.

Eighteen hip fusions were converted to total hip replacements. A constrained acetabular liner was used in 3 hips. Mean follow up was 5 years (2 to 15 years). Two (11%) hips failed, requiring revision surgery and two patients (11%) had injury to the peroneal nerve. Heterotopic ossification developed in 7 (39%) hips, in one case resulting in joint ankylosis. No hips dislocated.

Conversion of hip fusion to hip replacement carries an increased risk of heterotopic ossification and neurological injury. We advise prophylaxis against heterotopic ossification. When there is concern about hip stability we suggest that the use of a constrained acetabular liner is considered. Despite the potential for complications, this procedure had a high success rate and was effective in restoring hip function.

Impaction grafting is an excellent option for acetabular revision. It is technique specific and very popular in England and the Netherlands and to some degree in other European centers. The long term published results are excellent. It is, however, technique dependent and the best results are for contained cavitary defects. If the defect is segmental and can be contained by a single mesh and impaction grafting, the results are still quite good. If, however, there is a larger segmental defect of greater than 50% of the acetabulum or a pelvic discontinuity, other options should be considered.

Segmental defects of 25–50% can be managed by minor column (shelf) or figure of 7 structural allografts with good long term results. Porous metal augments are now a good option with promising early to mid-term results. Segmental defects of greater than 50% require a structural graft or porous augment usually protected by a cage. If there is an associated pelvic discontinuity then a cup cage is a better solution.

An important question is does impaction grafting facilitate rerevision surgery? There is no evidence to support this but some histological studies of impacted allograft would suggest that it may. On the other hand there are papers that show that structural allografts do restore bone stock for further revision surgery. Also the results of impaction grafting are best in the hands of surgeons comfortable with using cement on the acetabular side, and one of the reasons why this technique is not as popular in North America.

An expert panel of orthopaedic surgeons is going to be evaluating primary and revision total hip and total knee replacements submitted by the audience. Participants will present the x-rays and clinical findings of difficult cases for which they are seeking an expert opinion from the panel. The panel will probably have conflicting opinions which will lead to an entertaining and educational session. The moderator will also provide some extremely challenging cases once again, to stimulate more controversy. This session has been very popular in the past and is fast moving, humorous and educational.

An expert panel of orthopaedic surgeons is going to be evaluating primary and revision total hip and total knee replacements submitted by the audience. Participants will present the x-rays and clinical findings of difficult cases for which they are seeking an expert opinion from the panel. The panel will probably have conflicting opinions which will lead to an entertaining and educational session. The moderator will also provide some extremely challenging cases once again, to stimulate more controversy. This session has been very popular in the past and is fast moving, humorous and educational.

The indications for cementless acetabular fixation have been broadened because our data supports the use of trabecular metal cups even when there's limited bleeding host bone contact. Trabecular metal augments have allowed us to use cementless cups when there is segmental loss of bone.

Surgical Technique: The acetabular bed is prepared. If there is less medial bone stock than 2 mm, then morselised allograft is impacted by reverse reaming. When reaming is complete and less than 50% bleeding host bone is available for cup stabilization, then a trabecular metal cup is indicated.

Trabecular augments are used if the trabecular cup trial is not stable, or if it is uncovered by 40% or more. The conventional augments come in different sizes to accommodate the diameter of the cup and the size of the defect. Larger defects are addressed with anterior and posterior column augments, and superior defects with figure of seven augments. Augments are fixed with at least two screws. The interface between the cup and the augments should be stable, but some surgeons place a very thin layer of cement between the augment and cup so micromotion does not occur while ingrowth is occurring.

We have used trabecular metal augments in 46 acetabular revisions in conjunction with a trabecular metal cup. Thirty-four cases have at least 2 years follow-up with an average of 64.5 months. There has been 4 cup loosenings with 3 re-revisions.

Acetabular cages are necessary when an uncemented or cemented cup cannot be stabilised at the correct anatomic level. Impaction grafting with mesh for containment of bone graft is an alternative for some cases in centers that specialise in this technique.

At our center we use three types of cage constructs –

Conventional cage ± structural or morselised bone grafting. This construct is used where there is no significant bleeding host bone. This construct is susceptible to cage fatigue and fracture. This reconstruction is used in young patients where restoration of bone stock is important.

In our center the cup cage reconstruction is our most common technique where a cage is used, especially if there is a pelvic discontinuity.

Acetabular cages are necessary when an uncemented or cemented cup cannot be stabilised at the correct anatomic level. Impaction grafting with mesh for containment of bone graft is an alternative for some cases in centers that specialise in this technique.

At our center we use three types of cage constructs –

(A) Conventional cage ± structural or morsellised bone grafting. This construct is used where there is no significant bleeding host bone. This construct is susceptible to cage fatigue and fracture. This reconstruction is used in young patients where restoration of bone stock is important.

(B) Conventional cage in combination with a porous augment where contact with bleeding host bone can be with the ilium and then by the use of cement that construct can be unified. The augment provides contact with bleeding host bone and if and when ingrowth occurs, the stress is taken off the cage.

(C) Cup Cage Construct – in this construct there must be enough bleeding host bone to stabilise the ultra-porous cup which functions like a structural allograft supporting and eventually taking the stress off the cage. This construct is ideal for pelvic discontinuity with the ultra-porous cup, i.e., bridging and to some degree distracting the discontinuity. If, however, the ultra-porous cup cannot be stabilised against some bleeding host bone, then a conventional stand-alone cage must be used.

In our center the cup cage reconstruction is our most common technique where a cage is used, especially if there is a pelvic discontinuity.

A trochanteric osteotomy offers extensile exposure of the hip on both the acetabular and femoral sides. The classical trochanteric osteotomy which is transverse and involves a release of the vastus lateralis muscles is complicated by a significant incidence of trochanteric nonunion and more importantly, trochanteric migration. The trochanteric slide was designed to avoid trochanteric migration by keeping the trochanteric fragment in continuity with the abductors and the vastus lateralis. Even if there was a trochanteric nonunion, a trochanteric migration was prevented by continuity of muscles enclosing the greater trochanter in a sling of muscle.

When we first started doing the trochanteric slide, we used the technique originally described which involved starting with the posterior approach to take down the external rotators and the posterior capsule, and then proceeding with the trochanteric osteotomy. We found that our incidence of posterior dislocation increased to 15%. We therefore decided that we would attempt to do this operation but try to preserve the external rotators and the posterior capsule so they remained in situ attached to the main body of the femur, so that the trochanteric osteotomy was carried out just anterior to these muscles and posterior capsule. As a result of this our dislocation rate went from 15% to 3%.

This exposure provides an extensile exposure of the pelvis and femur. If femoral component removal is anticipated to be difficult, then we use exactly the same approach but we extend the trochanteric fragment down as in an extended trochanteric osteotomy.

An expert panel of orthopaedic surgeons is going to be evaluating primary and revision total hip and total knee replacements submitted by the audience. Participants will present the x-rays and clinical findings of difficult cases for which they are seeking an expert opinion from the panel. The panel will probably have conflicting opinions which will lead to an entertaining and educational session. The moderator will also provide some extremely challenging cases once again, to stimulate more controversy. This session has been very popular in the past and is fast moving, humorous and educational.

The indications for cementless acetabular fixation have been broadened because our data supports the use of trabecular metal cups even when there's limited bleeding host bone contact. Trabecular metal augments have allowed us to use cementless cups when there is segmental loss of bone.

The acetabular bed is prepared. If there is less than 2 mm medial bone stock, then morsellised allograft is impacted by reverse reaming. When reaming is complete and less than 50% bleeding host bone is available for cup stabilization, then a trabecular metal (TM) cup is indicated.

Trabecular augments are used if the trabecular cup trial is not stable, or if it is uncovered by 40% or more. The conventional augments come in different sizes to accommodate the diameter of the cup and the size of the defect. Larger defects are addressed with anterior and posterior column augments, and superior defects with figure of seven augments. Augments are fixed with at least two screws. The interface between the cup and the augments should be stable, but some surgeons place a very thin layer of cement between the augment and cup so micromotion does not occur while ingrowth is occurring.

We have used trabecular metal augments in 46 acetabular revisions in conjunction with a TM cup. Thirty-four cases have at least 2 years follow-up with an average of 64.5 months. There has been 4 cup loosenings with 3 re-revisions.

We still feel there is a role for structurally acceptable allografts in young patients who are likely going to require another revision. Our long term results have demonstrated that bone stock is restored facilitating the re-revision.

Acetabular cages are necessary when an uncemented or cemented cup cannot be stabilised at the correct anatomic level. Impaction grafting with mesh for containment of bone graft is an alternative for some cases in centers that specialise in this technique.

At our center we use three types of cage constructs: (A) Conventional cage ± structural or morselised bone grafting. This construct is used where there is no significant bleeding host bone. This construct is susceptible to cage fatigue and fracture. This reconstruction is used in young patients where restoration of bone stock is important; (B) Conventional cage in combination with a porous augment where contact with bleeding host bone can be with the ilium and then by the use of cement that construct can be unified. The augment provides contact with bleeding host bone and if and when ingrowth occurs, the stress is taken off the cage; (C) Cup Cage Construct – in this construct there must be enough bleeding host bone to stabilise the ultra-porous cup which functions like a structural allograft supporting and eventually taking the stress off the cage. This construct is ideal for pelvic discontinuity with the ultra-porous cup, i.e., bridging and to some degree distracting the discontinuity. If, however, the ultra-porous cup cannot be stabilised against some bleeding host bone, then a conventional stand-alone cage must be used.

In our center the cup cage reconstruction is our most common technique where a cage is used, especially if there is a pelvic discontinuity.

The indications for cementless acetabular fixation have been broadened because our data supports the use of trabecular metal cups even when there's limited bleeding host bone contact. Trabecular metal augments have allowed us to use cementless cups when there is segmental loss of bone.

Surgical Technique:

The acetabular bed is prepared. If there is less medial bone stock than 2mm, then morselised allograft is impacted by reverse reaming. When reaming is complete and less than 50% bleeding host bone is available for cup stabilization, then a trabecular metal cup is indicated.

Trabecular augments are used if the trabecular cup trial is not stable, or if it is uncovered by 40% or more. The conventional augments come in different sizes to accommodate the diameter of the cup and the size of the defect. Larger defects are addressed with anterior and posterior column augments, and superior defects with figure of seven augments. Augments are fixed with at least two screws. The interface between the cup and the augments should be stable, but some surgeons place a very thin layer of cement between the augment and cup so micromotion does not occur while ingrowth is occurring.

We have used trabecular metal augments in 46 acetabular revisions in conjunction with a TM cup. Thirty-four cases have at least 2 years follow-up with an average of 64.5 months. There has been 4 cup loosenings with 3 re-revisions.

Important issues related to total hip replacement for dysplasia are: placement of the cup and bone stock; the role of femoral osteotomy, and the choice of acetabular and femoral components.

The cup can be placed at the correct or near correct anatomical level with or without a bone graft, in a high position (high hip center) or at the right level in a protruded position. All three techniques can provide adequate coverage of the cup. In the high hip position bone graft is not usually necessary to obtain cup coverage. There is however a higher rate of component loosening, a higher dislocation rate, and lengthening is limited to the femoral side. Placing the cup in a protruded position to obtain coverage does not restore bone stock for future surgery, but it does place the hip at the correct level. Placing the cup in the correct anatomical position (i.e. at the right level and not protruded) may require a structural autograft which adds to the complexity of the case. However, bone stock is restored for future surgery. In a radiographic study of 31 shelf grafts with an average follow-up of 14 years, 22 grafts had mild resorption, and 9 moderate resorption. Ten patients required cup revision, 2 at 9 years, 2 at 10 to 15 years, and 6 at over 15 years. Only 2 hips required another structural graft.

Femoral osteotomy may be used as part of the exposure for diaphyseal shortening or for derotation of excessive anteversion. The osteotomy is carried out in the sub-trochanteric region and may be oblique, step-cut or transverse. Fixation of the osteotomy is achieved via the stem, a plate, or a cortical strut.

Cementless components are usually used because of the relatively young age of this patient population. Small components may be necessary. On the femoral side, the stem should be straight or modular so excessive anteversion can be neutralised.

Pelvic discontinuity with associated bone loss is a complex challenge acetabular revision surgery. Reconstruction by the use of ilio-ischial cages combined with trabecular metal acetabular components and morsellised bone (the component-cage technique) is a relatively new method of treatment. The trabecular cup provides a good environment for bone graft remodeling and eventual bone or fibrous ingrowth. The cage protects the trabecular metal cup until stabilisation occurs. The cage not only protects the cup but places the articulating center at the correct level.

We reviewed a consecutive series of 32 cases of acetabular revision reconstructions with pelvic discontinuity who had been treated by the cup-cage technique. The mean follow-up was 38 months (24.0 to 68.0). Failure was defined as a migration of a component of >5mm.

In 29 hips there was no clinical or radiological evidence of loosening at the last follow-up. The Harris hip scores improved significantly from 44.6 (sd 10.4) to 78.7 (sd 10.4) points (p<0.001).

In three hips (11.5%) the construct migrated at one year after surgery. The complications included two cases of dislocations, one of infection and one of partial palsy of the peroneal nerve. Our findings indicated that the treatment of pelvic discontinuity by the component-cage construct is a reliable option.

Cartilage repair strategies have been applied successfully to the knee, but only recently and with limited experience to the hip. The indications for these strategies have been well defined for the knee and are defined by the diameter and depth of the defects that are mainly post traumatic and degenerative.

Viscosupplementation is an intra-articular therapy that theoretically restores the protective effects of hyaluronic acid. This therapy has been widely used for osteoarthritis of the knee with some early preliminary promising results for osteoarthritis of the hip.

Microfracture can be performed arthroscopically or as part of an open procedure. This procedure is indicated for smaller lesions less than 3cm in diameter and 1cm in depth. Widely used in the knee, the results in the hip are limited but promising. The repair tissue is however fibrocartilage.

Autologous chondrocyte transplantation can yield hyaline like repair cartilage with good mid- to long-term results in the knee. The indications are chondral defects greater than 3cm in diameter or osteochondral defects less than 1cm in depth. Its use in the hip has been limited with only a few published papers. The procedure requires two stages. The first stage which involves harvesting the cartilage can be done arthroscopically, and the second stage which involves transplantation of the cultured chondrocytes can be done arthroscopically or open.

Larger lesions greater than 3cm in diameter and 1cm in depth, can be managed by osteochondral allografts. The published mid- to long-term results for the knee have been encouraging. The results for the hip are early. To date we have performed this procedure on 16 patients. Surgical dislocation of the hip is carried out via a trochanteric osteotomy and the defect defined and trephined out. A press-fit fresh osteochondral allograft is inserted using the trephine technique. We have published our early results on a series of 8 patients with 5 good to excellent results, 1 fair results and 2 failures.

The use of ilioischial cage reconstruction for pelvic discontinuity has been replaced by the Trabecular Metal (Zimmer, Warsaw, Indiana) cup-cage technique in our institution, due to the unsatisfactory outcome of using a cage alone in this situation. We report the outcome of 26 pelvic discontinuities in 24 patients (20 women and four men, mean age 65 years (44 to 84)) treated by the cup-cage technique at a mean follow-up of 82 months (12 to 113) and compared them with a series of 19 pelvic discontinuities in 19 patients (18 women and one man, mean age 70 years (42 to 86)) treated with a cage at a mean follow-up of 69 months (1 to 170). The clinical and radiological outcomes as well as the survivorship of the groups were compared. In all, four of the cup-cage group (15%) and 13 (68%) of the cage group failed due to septic or aseptic loosening. The seven-year survivorship was 87.2% (95% confidence interval (CI) 71 to 103) for the cup-cage group and 49.9% (95% CI 15 to 84) for the cage-alone group (p = 0.009). There were four major complications in the cup-cage group and nine in the cage group. Radiological union of the discontinuity was found in all successful cases in the cup-cage group and three of the successful cage cases. Three hips in the cup-cage group developed early radiological migration of the components, which stabilised with a successful outcome.

Cup-cage reconstruction is a reliable technique for treating pelvic discontinuity in mid-term follow-up and is preferred to ilioischial cage reconstruction. If the continuity of the bone graft at the discontinuity site is not disrupted, early migration of the components does not necessarily result in failure.

Cite this article: Bone Joint J 2014;96-B:195–200.

Hip osteoarthritis is prevalent in 8%–28% of patients with Down's Syndrome. Presence of disabling hip pain is increased along with prolonged life expectancy, suggesting total hip arthroplasty (THA).

Seven consecutive patients (9 hips) with Down's syndrome had primary THA. Coxarthrosis was secondary to developmental hip dysplasia in 6 patients and slipped capital epiphysis in 1 patient. In 5 patients (7 hips) a previous hip surgery was performed. Average clinical and radiological follow up was 9.9 ± 6.4 years (range 2–22.5, median 9.3). Average age of patients at THA was 34.8 ± 7.5 years (range 25–47, median 35.4). In 2 patients (3 hips) a trochanteric slide was used for the surgical approach, while a lateral transgluteal approach was used in the remaining patients. One way ANOVA test was used to compare Harris Hip Scores (HHS) at post-operative follow-up.

HHS improved significantly (p=0.008) improved from 4.1 ± 15.1 (range 18.5–65, median 45) to 84.3 ± 7.7 (range 70–93, median 85.8 at 4 year follow up. HHS (average 70.9 ± 6.2, range 66.5–80, median 68) remained essentially unchanged (p=0.43) at 8 year follow-up. Two patients required revision arthroplasty for stem loosening at 6 and 16 years post THA, respectively. The first patient is 7 years post revision and ambulates without aids. The second patient is 6.1 years post revision and ambulates with a walker. Six of the THAs required a constrained liner. No dislocations or deep infections were encountered.

THA is reliable surgical intervention in patients with Down's Syndrome and symptomatic coxarthrosis.

A trochanteric osteotomy offers extensile exposure of the hip on both the acetabular and femoral sides. The classical trochanteric osteotomy which is transverse and involved a release of the vastus lateralis muscles is complicated by a significant incidence of trochanteric nonunion and more importantly, trochanteric migration. The trochanteric slide was designed to avoid trochanteric migration by keeping the trochanteric fragment in continuity with the abductors and the vastus lateralis. Even if there was a trochanteric nonunion, a trochanteric migration was prevented by continuity of muscles enclosing the greater trochanter in a sling of muscle.

When we first started doing the trochanteric slide, we used the technique originally described which involved starting with the posterior approach to take down the external rotators and the posterior capsule, and then proceeding with the trochanteric osteotomy. We found that our incidence of posterior dislocation increased to 15%. We therefore decided that we would attempt to do this operation but try to preserve the external rotators and the posterior capsule so they remained in situ attached to the main body of the femur, so that the trochanteric osteotomy was carried out just anterior to these muscles and posterior capsule. As a result of this our dislocation rate went from 15% to 3%.

This exposure provides an extensile exposure of the pelvis and femur. If femoral component removal is anticipated to be difficult, then we use exactly the same approach but we extend the trochanteric fragment down as in an extended trochanteric osteotomy.

The indications for cementless acetabular fixation have been broadened because our data supports the use of trabecular metal cups even when there's limited bleeding host bone contact. Trabecular metal augments have allowed us to use cementless cups when there is segmental loss of bone.

Surgical Technique:

The acetabular bed is prepared. If there is less medial bone stock than 2 mm, then morsellised allograft is impacted by reverse reaming. When reaming is complete and less than 50% bleeding host bone is available for cup stabilisation, then a trabecular metal cup is indicated.

Trabecular augments are used if the trabecular cup trial is not stable, or if it is uncovered by 40% or more.

The conventional augments come in different sizes to accommodate the diameter of the cup and the size of the defect. Larger defects are addressed with anterior and posterior column augments, and superior defects with figure of seven augments. Augments are fixed with at least two screws.

The interface between the cup and the augments should be stable, but some surgeons place a very thin layer of cement between the augment and cup so micromotion does not occur while ingrowth is occurring.

We have used trabecular metal augments in 46 acetabular revisions in conjunction with a TM cup. Thirty-four cases have at least 2 years follow-up with an average of 64.5 months. There has been 4 cup loosenings with 3 re-revisions.

Introduction

A deficient abductor mechanism leads to significant morbidity and few studies have been published describing methods for reconstruction or repair. This study reports the reconstruction of hip abductor deficiency using human allograft.

Introduction

Revision hip arthroplasty with massive proximal femoral bone loss remains challenging. Whilst several surgical techniques have been described, few have reported long term supporting data. A proximal femoral allograft (PFA) may be used to reconstitute bone stock in the multiply revised femur with segmental bone loss of greater than 8 cm. This study reports the outcome of largest case series of PFA used in revision hip arthroplasty.

Primary total hip arthroplasty in patients with osteoarthrosis secondary to developmental hip dysplasia is often more complex due to anterolateral acetabular bone deficiency. Femoral head (shelf) autograft provides a non-immunogenic, osteoconductive lateral support with the potential for enhanced bone stock should revision surgery be required. The technique has been shown in other series to give reliable early results but may be complicated by graft revascularisation and collapse. As yet, no study has assessed shelf grafts long term or quantified the need for further bone graft at revision surgery.

This study aims to assess initial graft union rate; quantify long term graft resorption and; quantify the need for further bone graft in the patients requiring revision surgery.

A retrospective analysis of a single surgeon's series of 31 THR in 25 patients was conducted. Post-operative, biplanar radiographic analysis was performed at 3 and 6 months and annually thereafter for a mean of 14 years (range 8-18). Grafts were assessed for union, resorption and displacement. Intra-operative necessity for bone graft at revision surgery was recorded.

Union, osseous 93%, fibrous 7%. No grafts displaced. In 71% less than one-third of the graft resorbed, in 29% one-third to one-half resorbed and in no grafts did greater than a half resorb. Of 10 patients revised, 2 required bone graft for inadequate bone stock.

Femoral head autograft allows effective acetabular coverage with excellent rates of union, minimal graft resorption in the long term and improves bone stock in revision surgery.

Purpose: The purpose of this study was to evaluate the clinical effectiveness and outcomes of the ‘abductor sparing’ MIS Anterolateral approach (MIS Watson Jones/G3) in comparison to the MIS Direct Lateral and MIS Posterolateral approaches in primary total hip arthroplasty.

Method: A multicentre, prospective, randomized controlled trial was designed to evaluate for the superiority of the new MIS Anterolateral approach (MIS Watson Jones/ G3). The sample size calculation was performed for alpha .05, power .90, to evaluate for effect size 0.5 in WOMAC using repeated measures analyses with baseline WOMAC as covariate. A total of 156 patients consented to participate in the trial and patients were assigned to MIS Antero-lateral approach or alternate MIS approach (MIS Direct Lateral or MIS Posterolateral). Patients were subjected to standardized anaesthetic and perioperative management protocols and were evaluated at standardized intervals to evaluate endpoints of early recovery (3 months) as well as endpoints of 12 and 24 months respectively. The primary outcome of interest was WOMAC, however secondary outcomes included SF-36, as well as parameters of health resource utilization and complications. Univariate and multivariate analyses were perfomed.

Results: Patient groups were found to be similar at baseline with regards to demographics and baseline quality of life outcomes (p> .05). Multivariate and repeated measures analyses demonstrated no superiority of the MIS Anterolateral approach on outcomes of WOMAC and other quality of life measures in comparison to MIS Direct Lateral and MIS Posterolateral approaches (p> .05). Health care resource utlization was also similar with length of stay, blood transfusion requirements and complications (p> .05).

Conclusion: Our multicentre, prospective, randomized clinical trial demonstrates that the MIS Anterolateral approach is not superior to alternate MIS surgical approaches when evaluating outcomes of quality of life, complications, and health resource utilization. Surgeons should consider these outcomes, complications, and other relevant advantages and disadvantages of select surgical approaches when deciding on a technique for use in their orthopaedic practice.

Introduction: The objective for this study was to assess the long term results for minor column allograft used in revision hip arthroplasty.

Methods: We prospectively included patients undergoing acetabular cup revision using minor column allograft with a minimum of 5 years follow-up. Minor column allograft was used in uncontained acetabular bone defects of sizes between 30% and 50% of the acetabulum. Acetabular failures requiring re-revisions at any time after surgery were included. Acetabular failure for any cause requiring re-revision surgery was used as end-point. Graft failure was considered when re-revision required the concurrent use of structural bone graft, metal augments or excision arthroplasty for any cause.

Results: There were 65 cases that met the study criteria. We included 5 deaths with a mean follow-up of 11.9 years (6.8–14.8) and 10 losses to follow-up after a mean follow-up of 11.7 years (5.3–17.4). Twenty eight acetabulum failed, with 14 occurring before 5 years at a mean of 1.8 years (0.1–4.8) and 14 occurring after 5 years at a mean of 12.2 years (5.6–23.2). Causes included aseptic loosening (23), infection (2), dislocation (1), graft non-union (1) and cup fracture (1). Fourteen grafts failed, with 8 occurring before 5 years at a mean of 1.2 years (0.5–4) and 6 occurring after 5 years at a mean of 11.3 years (6–23.2) after surgery. The mean improvement in modified Harris Hip Scores was 32.3 at 1 year and 32.6 at last follow-up assessment. The cup survivorship was 56.9 % and graft survivorship 78.5 % at a mean follow-up of 16.3 years (5.3–24.8).

Discussion: Metal augments have been used in revision arthroplasty for low demand patients but we recommend the use of minor column allografts in higher demand patients who are more likely to require further revision surgery.

Purpose: An Osteochondral defect in the knees of young active patients represents a challenge to the orthopedic surgeon. Early studies on allogenic cartilage transplantation showed this tissue to be immunologically privileged, showed fresh grafts to have hyaline cartilage, and surviving chondrocytes present several years after implantation.

Method: Since January 1978 until October 1995 we enrolled 72 patients in a prospective non-randomized study of fresh osteochondral allografts in our institute. Ten international patients which were lost to follow-up were excluded. The major indications for the procedure were: patients younger than 60 years of age having post-traumatic unipolar defects larger than three cm in diameter and one cm in depth.

Results: Sixty two patients, ages 11–57 (mean 28) were followed for 15–31 years (mean 20.4 years). The etiology for the osteochondral defect was traumatic injury to the knee in 41 patients (66%), Osteochondritis Dissecans in 15 patients (24%), and in six patients (10%) due to other pre-existing conditions. Twenty of the 62 grafts have failed, with five having graft removal and 15 converted to total knee replacement. Three patients died during the course of this study due to unrelated causes. The Kaplan-Meier survivorship analysis showed: 92%, 79%, 56%, and 49% graft survival at 10, 15, 20, and 25 years respectively, (median survival = 23 years). Patients with surviving grafts had good function, with a modified Hospital for Special Surgery score of an average 88 at 20 years or more following the allograft transplantation surgery.

Conclusion: Through this long term study the authors confirm the value of fresh osteochondral allografts as a long term solution for large articular defects in the knees of young patients. The improvement of patients’ outcome compared to the previous published results of our earlier studies could be attributed to improved surgical techniques and increasing expertise of the senior authors. We therefore recommend the use of fresh osteochondral allografts for treatment of large osteochondral defects in the distal femur of young and active patients.

Objectives: Fresh osteochondral allografts are well-established treatment for patients who have posttraumatic osteochondral defects over 3cm in diameter and 1cm in depth of the knee. The objective of our study was to investigate the long-term outcome of these grafts and how long they may delay need for arthroplasty in patients with mal-united tibial plateau fractures.

Method: A prospective cohort study of patients who had received fresh osteochondral allografts of the tibial plateau was conducted. 118 patients were identified and survivor ship analysis was performed using conversion to total knee arthroplasty as the end point for graft failure. The Modified Hospital for Knee Surgery Scoring System (MHKSS) was used to clinically assess each patient who had more than five years of follow up. Radiographs were assessed for mechanical axis as well as using the Tonis grade for degenerative change.

Results: 29 of 118 (25%) experienced graft failure and underwent conversion to total knee arthroplasty, at a mean of 12 years (range 3–23) after the index procedure. The remaining 52 patients with a successful graft, and follow up over five years, had a mean MHKSS score of 83 (range 49–100) with a mean follow up of 11.7 years (range 5–34). Kaplan-Meier survivorship analysis of all 118 patients showed that graft survivorship was 94% at 5 years (std err 2.7), 83% at 10 years (std err 4.6), 62% at 15 years (std err 7.4) and 45% at 20 years (std err 8.5). Factors that predicted a successful graft were, using a meniscal allograft in conjunction with the osteochondral graft, and a lateral tibial plateau defect. The age at the time of surgery was no different between the patients that had a successful graft or those that failed.

Conclusion: Fresh osteochondral allografting works well in providing long term treatments for patients with tibial plateau damage. The concurrent use of meniscal allografts is also recommended.

Management of massive acetabular defects in revision hip arthroplasty is challenging. The current generation reconstruction cages in combination with either morcellised or structural allograft bone have given promising results. However, a significant number fail due to failure of biological fixation of the cage, resulting in fatigue fracture of the cage. Trabecular metal has the potential to enhance biologic fixation. The purpose of this paper is to introduce this new surgical technique of combining a cage with a shell of trabecular metal and present the early results.

Fourteen patients (mean age 63, range 45 to 82 years) with massive contained defects underwent revision arthroplasty with a cup cage by the senior author (AEG). Complications, functional status (WOMAC, Oxford hip score and SF36) and radiographs were assessed. Post operative radiographs were assessed for evidence of construct migration, resorption and or remodelling of allograft bone. Remodelling was defined by the presence of bony trabeculae crossing the allograft host junction. Lucent lines were assessed. Allograft resorption was defined as loss of graft height on comparable radiographic views. An implant was defined as loose if there was evidence of construct migration or component fracture.

The mean follow up was 21 months (range one to 38 months). Complications included one death and one recurrent dislocation requiring revision to a capture liner. Average pre and post operative WOMAC scores were 61 and 17 points respectively. Oxford hip scores were an average of 45 pre-operatively and 24 post-operatively. SF-36 averaged 351 pre-op and 601 post-op. All implants were stable. Minor radiolucent lines were found around the inferior flange of the cage in six patients. Minor graft resorption occurred in two patients. All but one showed graft remodelling. All patients were ambulant.

The early results of this new technique for treating a complex problem show excellent rates of initial implant stability and bone graft remodelling.

We reviewed and discussed the results of one hundred and fifty-five proximal femoral allografts for revision total hip replacement at an average of eleven years (range , five to twenty years).We looked at graft survivorship, functional results, radiographic assessment and complications. We concluded that this is an excellent technique for restoration of bone stock in the multiplied revised hip.

To review the results of revision hip replacement with use of a proximal femoral allograft (PFA) to restore femoral bone stock.

Between 1983 and 1998 a PFA – prosthetic composite was used to revise two hundred and twenty-seven hips in two hundred and ten patients. Of these two hundred and ten revisions involved an allograft longer than 8 cm. The average age of the patients at the time of revision was sixty-six years. The average number of previous total hip replacements was 2.2. Each patient was assigned a SF-12 score and a Short WOMAC Score. Radiographic assessment for trochanteric union, allograft-host union, component stability, graft fracture and resorption was performed.

At an average of 11.2 years ( range, five to twenty years) after the revision, one hundred and eighty-five patients were alive, twenty-five patients had died and thirty were unavailable for follow-up. SF-12 and short WOMAC scores are still being calculated at the time of abstract submission. 4.4% of hips failed due to infection with 50% being successfully revised. Aseptic loosening of the construct occurred in 3.9% and 78% of these were revised at the time of follow-up. Nonunion of the allograft-host junction occurred in 4.8% and dislocation in 8.4%. Success was defined as a stable implant and no need for additional surgery at the time of follow-up. Success was noted in 84% of available cases.

At an average of eleven years revision hip arthroplasties with a PFA are performing very well. This technique remains an excellent alternative when confronted with femoral bone loss in the revision hip setting.

This is a retrospective study of fifty nine hips in fourty nine patients with a previous total hip replacement for developmental dysplasia of the hip who underwent a revision arthroplasty of the hip. Fifty three patients were available for follow up. Radiographs and charts were reviewed and functional outcome scores were obtained in order to determine if a correlation existed between cup position and functional outcome and survivorship. Cup height was found to be a statistically significant predictor for functional outcome and cup survivorship.

To determine if cup height, lateralization or angle are correlated with functional outcome or survivorship in revision total hip replacement (THR) in patients with a previous THR for developmental dysplasia of the hip (DDH).

There is a paucity of literature correlating functional outcome with cup position in revision THR.

Cup height was found to have a statistically significant (p< 0.05) correlation with Harris Hip, SF36, and WOMAC functional scores. High hip centers correlated with worse scores. In addition, patients with hip centers less than 3.5 cm above the radiographic tear drop had a statistically significant improvement in cup survivorship compared to those with higher hip centers.

A retrospective investigation of forty-nine sequential patients (fifty-nine hips) previously diagnosed with DDH who underwent revision THR at our center between 1984 and 2000 was performed. Forty-three patients (fifty-three hips) were available for survivorship analysis and thirty-five patients (forty-five hips) were available for functional analysis. The mean follow up was one hundred and eighteen months (range 36–230). Three independent variables identified apriori as possible correlates were cup height, lateralization and angle as measured on the AP radiographs. Functional outcome measurement consisted of the Harris Hip, SF36 and WOMAC questionnaires. Linear regression analysis and Kaplan-Meier curves were used to determine if any of the variables correlated with functional outcome or survivorship.

Restoration of hip center height to as close to the radiographic tear drop as possible improves functional outcome. Placement of the cup to within 3.5 cm of the tear drop improves cup survivorship.

We reviewed and discussed the results of thirteen distal femoral allografts in conjunction with revision total knee arthroplasty for the treatment of periprosthetic femoral supracondylar fractures associated with poor bone stock. The mean follow up time was six years. We looked at graft survivorship, functional outcome, radiographic assessment, and complications. We concluded that this is a viable salvage procedure for this type of injury.

The incidence of periprosthetic supracondylar fractures of the femur is rising due to the aging population, and the increased number of total knee arthroplasties (TKA) being performed. One option for the treatment of severe fractures, associated with poor bone stock, is the use of a distal femoral allograft (DFA) in conjunction with revision TKA. The purpose of this study was to review and discuss the results of thirteen consecutive patients who were treated at our center between 1990 and 2001.

Data was obtained from a prospective database. Ten of the thirteen patients were available for follow up. The average age was sixty-five years (range twenty-four to ninety-three) and the mean length of follow up was six years (range one to twelve). A chart review was performed to identify complications and graft survivorship. Functional assessment was made on the basis of the modified Hospital for Special Surgery knee score (HSS) and the MOS 36-ITEM Short Form Health Survey (SF-36). Patients were evaluated radiographically by two independent observers (kappa = 0.75, P = 0.02) in an attempt to determine union between the graft and host bone, graft resorption, and component loosening. The average postoperative HSS score and SF-36 were seventy-five and eighty-eight respectively. Mean flexion was 100°. One had an amputation due to the recurrence of infection. X-rays showed no migration, no loosening, good interface union in nine cases and mild to moderate resorption in three cases. We concluded that this is a viable salvage procedure for this type of injury.

Notching of the anterior femoral cortex during total knee arthroplasty is thought to be a possible risk factor for subsequent periprosthetic femoral fracture. Understanding the stress pattern caused by notching may help the orthopedic surgeon reduce the risk of fracture. A validated, three dimensional, finite element model of the femur using gait loads has been used to analyze the stress concentrations caused by anterior femoral cortex notching. Three factors that increase these stresses were identified. The notch depth, radius of curvature, and its proximity to the end of the femoral prosthesis influence the state of stress in the surrounding bone.

The purpose of this study was to characterize the stress concentration caused by anterior femoral notching during total knee replacement (TKR) in order to determine when a patient is at risk for a periprosthetic fracture of the femur.

We concluded that notches greater than 3 mm with sharp corners located directly at the proximal end of the femoral implant produced the highest stress concentrations and may lead to a significant risk of periprosthetic femur fracture.

One complication that can occur during TKR is notching of the anterior femoral cortex which results in a stress concentration. It is important to characterize this stress riser in order to determine when a stemmed femoral component should be used to minimize the risk of fracture.

Three factors that affected the stress concentration were identified. First, increasing the notch depth lead to significant increased stress concentrations. When the depth was greater than 3 mm, local stresses increased markedly. Second, the radius of curvature was found to be inversely related to stress concentration. As the radius decreased, the local stress increased. Third, the proximity of the notch to the prostheses affected the stress concentration. Notches that were 1 mm proximal to the implant resulted in much larger stresses than those that were 10 mm away.

A validated, three dimensional finite element model of a femur subjected to a gait loading pattern was used to characterize the stress concentration caused by anterior femoral notching. The results compared well to previous work reported in the literature.

Periprosthetic fracture management after hip arthroplasty is complicated by poor bone stock and loose femoral components. Using a prospective database, thirty-five fractures treated by proximal femoral allograft reconstruction were identified. Patients treated between 1989–2000 with minimum two- year results, were reviewed at a mean of 3.8 years. Twenty-six fractures were acute, and nine had failed previous treatment. Union of the PFA was achieved in all but five cases (83%). In twenty-eight cases (78%) no further surgery was required and patient ambulation was pain free. When conventional treatment is not possible, the use of a PFA provides encouraging results.

Periprosthetic femoral fracture treatment is complicated by comminution, bone loss, and potentially loose femoral components. Treatment can include cast-braces, internal fixation, revision arthroplasty or the use of proximal femoral allograft composites (PFA). This study reports on thirty-five fractures treated with a PFA between 1989–2000. Five patients were lost and twelve patients (33%) were deceased. Follow-up averaged 3.8 years (range 0.1–11.3) with minimum two-year results in surviving patients. Six patients had either Rheumatoid arthritis or DDH with very narrow femoral canals.

There were twenty-three acute fractures, five failures of non-operative management, four failures of ORIF and two fractured femoral stems. Fractures were classified by the Vancouver system with: B1–7%, B2–30%, B3–43% and C-20%. Prefracture functional scores revealed that 30% of patients had significant functional impairment and were awaiting revision arthroplasty. Patients had had an average of two previous surgical procedures (range 1–4).

The mean length of the PFA was 14cm and union between graft and host bone was achieved in all but five cases (83%). Resorption of the graft was seen in eight cases (27%), lucent lines in six cases (20%) and implant migration in four cases (13%). Post revision arthroplasty Harris Hip and SF-36 scores revealed substantial disability in this patient group.

Twenty-eight cases (73%) were deemed successful with patients not requiring further surgery and enjoying pain free ambulation. In fractures with unstable femoral components and inadequate bone stock or very narrow femoral canals few options are available. This technique provides encouraging results and a viable option when conventional treatment is not possible.

Notching of the anterior femoral cortex during total knee arthroplasty is thought to be a possible risk factor for subsequent periprosthetic femoral fracture. Understanding the stress pattern caused by notching may help the orthopedic surgeon reduce the risk of fracture. A validated, three dimensional, finite element model of the femur using gait loads has been used to analyze the stress concentrations caused by anterior femoral cortex notching. Three factors that increase these stresses were identified. The notch depth, radius of curvature, and its proximity to the end of the femoral prosthesis influence the state of stress in the surrounding bone.

The purpose of this study was to characterize the stress concentration caused by anterior femoral notching during total knee replacement (TKR) in order to determine when a patient is at risk for a periprosthetic fracture of the femur.

We concluded that notches greater than 3 mm with sharp corners located directly at the proximal end of the femoral implant produced the highest stress concentrations and may lead to a significant risk of periprosthetic femur fracture.

One complication that can occur during TKR is notching of the anterior femoral cortex which results in a stress concentration. It is important to characterize this stress riser in order to determine when a stemmed femoral component should be used to minimize the risk of fracture.

Three factors that affected the stress concentration were identified. First, increasing the notch depth lead to significant increased stress concentrations. When the depth was greater than 3 mm, local stresses increased markedly. Second, the radius of curvature was found to be inversely related to stress concentration. As the radius decreased, the local stress increased. Third, the proximity of the notch to the prostheses affected the stress concentration. Notches that were 1 mm proximal to the implant resulted in much larger stresses than those that were 10 mm away.

A validated, three dimensional finite element model of a femur subjected to a gait loading pattern was used to characterize the stress concentration caused by anterior femoral notching. The results compared well to previous work reported in the literature.

Periprosthetic fracture management after hip arthroplasty is complicated by poor bone stock and loose femoral components. Using a prospective database, thirty-five fractures treated by proximal femoral allograft reconstruction were identified. Patients treated between 1989–2000 with minimum two- year results, were reviewed at a mean of 3.8 years. Twenty-six fractures were acute, and nine had failed previous treatment. Union of the PFA was achieved in all but five cases (83%). In twenty-eight cases (78%) no further surgery was required and patient ambulation was pain free. When conventional treatment is not possible, the use of a PFA provides encouraging results.

Periprosthetic femoral fracture treatment is complicated by comminution, bone loss, and potentially loose femoral components. Treatment can include cast-braces, internal fixation, revision arthroplasty or the use of proximal femoral allograft composites (PFA). This study reports on thirty-five fractures treated with a PFA between 1989–2000. Five patients were lost and twelve patients (33%) were deceased. Follow-up averaged 3.8 years (range 0.1–11.3) with minimum two-year results in surviving patients. Six patients had either Rheumatoid arthritis or DDH with very narrow femoral canals.

There were twenty-three acute fractures, five failures of non-operative management, four failures of ORIF and two fractured femoral stems. Fractures were classified by the Vancouver system with: B1–7%, B2–30%, B3–43% and C-20%. Prefracture functional scores revealed that 30% of patients had significant functional impairment and were awaiting revision arthroplasty. Patients had had an average of two previous surgical procedures (range 1–4).

The mean length of the PFA was 14cm and union between graft and host bone was achieved in all but five cases (83%). Resorption of the graft was seen in eight cases (27%), lucent lines in six cases (20%) and implant migration in four cases (13%). Post revision arthroplasty Harris Hip and SF-36 scores revealed substantial disability in this patient group.

Twenty-eight cases (73%) were deemed successful with patients not requiring further surgery and enjoying pain free ambulation. In fractures with unstable femoral components and inadequate bone stock or very narrow femoral canals few options are available. This technique provides encouraging results and a viable option when conventional treatment is not possible.

1069 primary hip arthroplasty (THA) (416 males) and 1846 revision (798 males) patients were matched for sex, age and date of primary THA. Data were collected via retrospective chart review. Time to revision averaged 9.5 years. Revision THA patients were younger at primary THA (55 vs. 64 years), had a higher body mass index (27 vs. 30) and more frequently had a cemented acetabulum (p< 0.0001). After controlling for institution, earlier time to revision was predicted by younger age at primary THA, secondary OA or dysplasia, increased BMI, posterior surgical approach, cemented acetabulum, and small femoral head size (28 mm) (p< 0.05).

To determine whether patient (age, gender, underlying disease, body mass index), surgical (surgical approach), and prosthetic (cemented vs. uncemented acetabular or femoral component, femoral head size) factors predict time to revision arthroplasty of primary total hip arthroplasty (THA).

Patients who are younger when undergoing primary THA, have secondary osteoarthritis (OA) or dysplasia, are obese, and have a cemented acetabulum with a small femoral head by a posterior approach are at increased risk for revision THA.

This study identified important, potentially modifiable patient, surgical and prosthetic factors that are adverse predictors of outcome.

For the period 1980 to 2000, 1069 primary hip arthroplasty patients (416 males) and 1846 revision arthroplasty (798 males) patients were matched for sex, age and date of primary THA within two years. Revision THAs for infection were excluded. Data were collected via retrospective chart review. Time to revision THA averaged 9.5 years. In univariate analysis, patients who had revision THA were younger at primary THA (55 vs. 64 years, p< 0.0001), had a higher body mass index (BMI) (27 vs. 30, p< 0.0001), and more frequently had a cemented acetabulum (p< 0.0001). After primary THA, fewer patients who went on to revision arthroplasty had orthopaedic complications (6.5 vs. 16.5%). After controlling for institution, earlier time to revision was predicted by younger age at primary THA, underlying joint disease of secondary OA or dysplasia, increased BMI, posterior surgical approach, cemented acetabulum, and small femoral head size (28 mm) (multivariate Cox model, p< 0.05).

Funding: This work was supported in part by a grant from the Canadian Orthopaedic Foundation and The Arthritis Society

This study (n=126, mean age=68.8 years, males=62) evaluated pre-operative WOMAC pain and physical function, age, gender, general health status, revision severity classification, number of revisions, comorbidity and unilateral vs. bilateral surgery as predictors of WOMAC pain and physical function at twenty-four months post revision hip arthroplasty. Pain improved from 9.3 to 3.6 and physical function improved from 35.4 to 17.1. No factors were predictive of patient function. Decreased pain was predicted by less pain pre surgery (p=0.01) and being male (p=0.04).

To determine if pre-operative WOMAC pain and physical function, age, gender, general health status (SF-36), revision severity classification, number of revisions, comorbidity and unilateral vs. bilateral surgery are predictive of WOMAC pain and physical function at twenty-four months post revision hip arthroplasty.

Physical function at twenty-four months is not independently predicted by the pre-treatment factors evaluated in this study. Male patients with less pain pre surgery and little comorbidity have less pain post surgery.

With the exception of pre-treatment pain, the pre-treatment factors tested in this study provide minimal guidance in identifying factors that might be modified to enhance patient outcome.

This prospective cohort study included one hundred and twenty-six patients (mean age=68.8 years, males: females=62:64) who had revision for other than infection or peri-prosthetic fracture. On average from pre-surgery to twenty-four months post-surgery, WOMAC pain improved 9.3 to 3.6 and physical function improved from 35.4 to 17.1. In univariate analysis (t-test, p< 0.05), males tended to have better function (19.6 vs. 14.7) and reported less pain (4.4 vs. 2.8). No other factors were significant in univariate analysis. None of the a priori factors noted above were independently predictive of patient function at twenty-four months in the multivariate model (F=2.06, p=0.04, R²=0.16). Decreased pain with activity at twenty-four months independently was predicted by having less pain pre surgery (p=0.01), being male (p=0.04) and having fewer comorbidities (p=0.07) in the multi-variate model (F=2.9. p=0.004, R²=0.21).

Funding: This work was supported by a grant from The Arthritis Society

Purpose: Many surgeons are now performing hip arthroplasty using a minimally invasive technique with the aim of reducing muscle damage and improving rehabilitation. We compared the learning curve of two MIS THA approaches: the two-incision mini and a modified Watson-Jones (G3) approach.

Methods: A retrospective review of 47 consecutive patients who underwent a THA using an MIS approach was conducted. All patients received an uncemented acetabular cup (Trilogy–Zimmer) fixed with 1 or 2 screws, and an uncemented femoral stem (ML taper, fiber metal taper, fully porous coated–Zimmer). Note was made of BMI, surgical time, incision length, blood loss, component positioning, hospital stay and perioperative complications.

Results: Twenty-one patients received a G3 and 26 received a 2 incision mini approach. The average BMI was 29.7 and 26.1 respectively. Average acetabular inclination was 37 for the G3 and 42 for the 2-incision mini. On average, the femoral component was positioned in neutral in the coronal plane for both approaches. Average surgical time was 121minutes for the G3 and 166 minutes for the 2-incision which also includes fluoros-copy time. Hospital stay averaged 5.4 and 6.8 days respectively. The skin incision averaged 8.9 cm for G3 a total of 9.8cm for 2-incision. Perioperative complications for the G3 included 1 lateral femoral cutaneous nerve palsy, 1 DVT, 1 PE and 1undisplaced intraoperative acetabular fracture. Complications for the 2-incision mini included 5 intraoperative fractures, 7 nerve injuries, 1 wound infection, 1 infection requiring revision and 1 PE.

Conclusions: The G3 minimally invasive approach for THA has advantages over the 2-incision mini: shorter operative time, no need for fluoroscopy, fewer days in hospital, shorter total incision length and lower complication rate. The G3 approach also offers the opportunity to bail out to a traditional approach, by extending the incision, should this be necessary.

Introduction: Distal femoral varus osteotomy (DFVO) has been advocated as the treatment of choice for lateral compartment osteoarthritis associated with a valgus knee in the young population in order to delay the need for total knee arthroplasty (TKA). The aim of this study was to evaluate the long-term results of DFVO for the valgus osteoarthritic knee.

Methods: A retrospective analysis was performed on 38consecutive patients (40 knees) who underwent a DFVO between 1984 and 2001. Two patients (2 knees) were lost to follow-up. Mean follow up was 123 months (range 39 to 245 months). Peri-operative documentation was evaluated for etiology, pre-operative functional and subjective impairment, intra-operative technical difficulties or complications, early and late post-operative complications and post-operative functional and subjective outcomes.

Results: At the time of the most recent follow-up, 24 knees had good or excellent result, 3 knees had a fair result and 3 had poor results. The remaining 8 knees were converted to a total knee arthroplasty. The mean Knee Society objective score improved from 18 (range, 0–74) to 87.2 (range, 50–100) and the mean Knee Society function score improved from 54 (range, 0–100) to 85.6 (range, 40–100). The ten-year survival rate of DFVO was 82% (95% confidence interval, 75%–89%) and the fifteen-year survival rate was 45% (95% confidence interval, 33%–57%).

Discussion: With proper patient selection, DFVO is a reliable procedure for the treatment of the valgus osteoarthritic knee. This procedure delays the need for further surgical procedures, such as TKA, with good results.

Background: Revision total hip replacement in patients with a previous diagnosis of developmental dysplasia of the hip (DDH) can be a challenging and technically demanding procedure. Two of the major concerns are deficient acetabular bone stock and the position of the acetabular implant, particularly if the hip centre was not restored during the primary procedure. The purpose of this study was to determine if cup height, lateralization or abduction angle are correlated with functional outcome or survivorship in revision total hip replacement (THR) in patients with a previous diagnosis of DDH.

Methods: A retrospective investigation of 51 sequential patients (63 hips) previously diagnosed with DDH who underwent revision THR at our center between 1984 and 2000 was performed. The mean duration of follow up was 119 months (range 36 to 238 months). Forty-one patients (52 hips) were available for functional outcome and survivorship analysis. The remaining ten patients (11 hips) were available only for survivorship analysis. Three independent variables identified apriori as possible correlates were cup height, lateralization and angle as measured on the AP radiographs. Functional outcome measurement consisted of the Harris Hip, SF36 and WOMAC questionnaires. Linear regression analysis and Kaplan-Meier curves were used to determine if any of the variables correlated with functional outcome or survivorship.

Results: Cup height was found to have a statistically significant (p< 0.05) correlation with Harris Hip, SF36, and WOMAC functional scores. High hip centers correlated with worse scores. In addition, patients with hip centers less than 3.5 cm above the radiographic tear drop had a statistically significant improvement in cup survivorship compared to those with higher hip centers.

Conclusion: Restoration of hip center height to as close to the radiographic teardrop as possible improves functional outcome and cup survivorship.

Purpose: Prevalence of supracondylar fractures above a total knee arthroplasty (TKA) is increasing due to the increasing age of treated patients and the larger number of implants. We report the functional results in a series of thirteen patients treated with a distal femoral graft (DFG) associated with revision TKA.

Material and methods: Between 1990 and 2001, thirteen patients (twelve women and one man), mean age 65 years (24–93) were treated with DFG associated with revision TKA. All fractures were type III using the Lewis classification and involved severe osteoporotic bone associated with loosening of the femoral piece. Before fracture, the patients had had two operations on average (1–4). The fracture occurred as a result of a fall in nine patients, low-energy trauma in three, and during mobilisation under general anaesthesia in one. The functional results were noted prospectively using the modified HSS score and the SF-36 quality-of-life questionnaire. Radiographic assessment of bone healing and implant stability was performed by two independent observers (kappa=0.75, p=0.02).

Results: At mean follow-up of 60 months (12–144), the mean HSS score was 75 (64–86). Mean knee flexion was 100° (50–115°). One patient required subsequent amputation due to infection. Using our classification, functional outcome was good or excellent in seven patients, fair in four and poor in two. For nine patients, x-rays showed no sign of loosening. In three patients, there was minimal to moderate periprosthetic bone resorption.

Discussion: Treatment of periprosthetic fractures of the knee is a therapeutic challenge. Osteoporosis and comminution is a complex association making stable osteo-synthesis difficult with conventional methods. Massive knee prosthesis using a DFG and a standard TKA is an attractive alternative. This technique allows restoration of the bone stock by bone healing and constitutes a less aggressive therapeutic solution.

Conclusion: Despite the risk of infection, we believe that composite prostheses can be an attractive option for the treatment of periprosthetic supracondylar fractures of the knee.

Introduction: To evaluate the medium-term outcome of patients undergoing revision knee arthroplasty with structural allograft for uncontained defects.

Methods: We followed prospectively 50 patients undergoing 52 revision knee replacements with 66 structural grafts in three institutions. An independent investigator reviewed twenty-nine knees in 27 patients after a mean of 96.9 months.

Results: Twelve knees were re-revised at a mean of 70.7 months. Two of these patients retained their allografts. Eleven patients died with their structural allograft and implants intact and were not awaiting revision at a mean of 93 months.

Failure was defined as an increase of less than 20 points in the modified HSS knee score at the time of the review or the need for an additional operation related to the allograft. Thirteen knees were deemed to be failures giving a 75% success rate. Graft resorption occurred in five patients resulting in implant loosening. Four failed due to infection and non-union between the host bone and allograft was present in two. One patient with both knees grafted failed to gain a 20-point improvement. Survival analysis showed a 72% survival at 10 years. Clinically, the modified HSS score improved from a mean of 32.5 pre-operatively to 75.6 at the time of the review. Radiographic analysis of the surviving grafts showed no severe resorption, one moderate and two mild cases of resorption. Evaluation for loosening revealed one patient with a loose tibial component, while three patients had non-progressive tibial radiolucent lines. All four patients were asymptomatic.

Conclusions: Our results demonstrated encouraging medium-term survival of allografts utilised for revision knee replacement in a group of difficult patients with massive bone loss.

Aim: Proximal femoral allografts are a rare but valuable option in severe femoral bone loss in revision hip arthroplasty. However, there are no long-term follow-up reports on their use. The purpose of this study was to review the average 11-year results of massive proximal femoral allografts used for severe bone loss in revision hip arthroplasty.

Method: Sixty-three total hip arthroplasties in 60 consecutive patients were revised with a proximal femoral allograft and a prosthesis. The mean length of the allograft was fifteen centimeters. All patients had undergone at least one previous total hip arthroplasty, with a mean of 3.8 operations. Each patient was assessed before operation and at follow-up with a modified Harris hip score and radiographs.

Results: At a mean follow-up of 11 years (range: nine to 15 years), 45 patients (75%) were alive, 14 patients (23 %) were deceased and one patient was lost to follow- up. The average preoperative Harris hip score was 30 points; at the latest follow-up the average score of those with the original graft in situ was 71. The deceased and lost patients represented 15 allografts (24%) with an average of five years and seven months follow-up. There were five failures for infection, four of which were successfully revised. Three hips failed with aseptic loosening at average 10 years and three months, two have been successfully re-revised and the third is awaiting revision. Success was defined as a postoperative increase in the Harris hip score of greater than twenty points, a stable implant, and no need for further surgery related to the allograft at the time of review. The success rate for all patients was 78% at an average of nine years follow-up. The success rate of those living was 77% at an average of 11 years follow-up.

Conclusion: At an average of 11-years following proximal femoral allografts the clinical and radiological results were encouraging.

For the surgical approach a trochanteric osteotomy should be utilised if lengthening is to be carried out. The leg can be lengthened up to 4 cm but the nerve should be monitored by exploration, a wake up test, or electrical monitoring.

Bone grafting for reconstruction of the dysplastic acetabulum in total hip arthroplasty has certain distinct advantages. It provides bone support for the acetabular prosthesis at the correct or near correct level. It restores anatomy and corrects leg lengths. It restores bone stock for future surgery. The alternatives, the high hip center, or medialisation are acceptable if adequate bone stock is available and leg lengths are not a problem (i.e. bilateral disease). The potential problem of these two techniques is that they do not restore bone stock for future surgery.

Cemented or uncemented components can be used. Small straight stems must be available in order to fit the dysplastic femur. Most implant designs carry CDH components. The dysplastic femur is not only small in diameter, but also excessively anteverted. If an anatomic stem is used it will be too anteverted. A straight narrow stem allows the surgeon to position the stem correctly.

Between May of 1982 and May of 1994, 67 hips in 58 patients underwent total hip replacement for congenital dislocation with the use of bulk autograft to augment the acetabulum. The average follow-up was 10 years. The revision rate for the cups was 16% (11 hips), and for the stem 6% (four hips). The clinical and radiographic failure rate for the 67 hips was 25% (12 revised, one waiting revision, and four definitely loose). The Kaplan-Meier survivorship for the cups at 14 years was 78%, and the stem 85%. There were three graft nonunions all of which required revision. Resorption of over one-third occurred in 10% of grafts (seven grafts), with four requiring further revision, but only one requiring another structural graft.

Articular defects in the knee can be managed by surface treatments, cartilage cell transplantation, periosteal grafts, osteochondral autografts, and osteochondral allografts. The factors, which determine the most appropriate treatment, are the size of the defect, and the associated bone loss. If there is an associated deformity, all of the aforementioned techniques would be combined with osteotomy.

Chondral defects with no significant bone involvement can be managed arthroscopically by surface treatments like debridement and drilling, abrasion arthroplasty, and microfracture. Chondral defects can also be managed arthroscopically by osteochondral autografts (mosaicplasty) or by cartilage cell transplant or periosteal grafts, both of which are done by open surgery. The arthroscopic surface treatments are best reserved for small defects but cell transplantation and mosaicplasty have been used for defects up to 2 cm in diameter. Periosteal grafting can be used for large defects affecting an entire condyle, but clinical experience with this procedure is limited and it is still considered experimental.

Articular defects that involve bone can to some degree be treated by mosaicplasty if the bone defect is contained and less than 1 cm in depth.

Larger osteochondral defects are managed by osteochondral allografts (uncontained defects greater than 3 cm in diameter and greater than 1 cm in depth). The disadvantage of osteochondral allografting is that it requires an open procedure and there is the potential for disease transmission.

The author has published a series of 126 knees in 123 patients with major post-traumatic osteochondral defects treated by allografts. At an average follow-up of 7.5 years the success rate was 85%. Retrieval studies have confirmed hyaline cartilage.

In a recent study of 40 patients with femoral condylar grafts for trauma or osteochondritis dissecans, at an average follow-up of 11 years, the survivorship was 80%.

Roof reinforcement and reconstruction rings have facilitated bone restoration in revision arthroplasty of the acetabulum. These rings are used when there is not enough bone to support a conventional cemented or a standard sized or jumbo uncemented cup. Both rings may be used with morselised or structural allograft bone. Roof reinforcement rings are used for contained defects but contact must be made with host bone superiorly and infero-medially. For more global contained defects where most of the acetabulum is filled with morselised allograft bone, contact with host acetabulum infero-medially is impossible. Under these circumstances a reconstruction ring that extends from ilium to ischium must be used.

Uncontained (segmental) bone defects reconstructed with structural allografts are bridged and protected by reconstruction rings that extend from ilium to ischium.

In 43 acetabular revisions, roof reinforcement rings were used with morselised allograft bone for contained defects. At five years average follow-up the survivorship was 88% (one re-revision and four definitely loose).

In 13 patients with massive uncontained acetabular defects, reconstruction rings were used in conjunction with structural allografts. At an average follow-up of 10.5 years, the survivorship was 77% (10 hips have not been re-revised and have a stable implant).

We report 11 patients having revision of total hip arthroplasty using massive structural allografts for failure due to sepsis and associated bone loss. All patients had a two-stage reconstruction and the mean follow-up was 47.8 months (24 to 72). Positive cultures were obtained at the first stage in nine of the 11 patients, with Staphylococcus epidermidis being the most common organism. The other two patients had draining sinuses with negative cultures.

There was no recurrence of infection in any patient. The mean increase in the modified Harris hip score was 45 and all the grafts appeared to have united to host bone. Two patients required additional procedures, but only one was related to the allograft. Complications included an incomplete sciatic nerve palsy and one case of graft resorption. Our results support the use of massive allografts in failed septic hip arthroplasty in which there is associated bone loss.

We report two cases in which arthrodesed knees were revised to total arthroplasties after the use of soft-tissue expanders. Case 1 had had multiple operations on her knee and had been arthrodesed for septic arthritis two years earlier. Case 2 had had knee arthrodesis for severe osteoarthritis 18 years before revision. In both patients, tissue expanders were used to increase the soft tissues available for cover and to help to mobilise the extensor mechanism. The operations were made much easier, and in both patients a range of motion from 0 degrees to 90 degrees was achieved at operation.

We reviewed 32 deep-frozen irradiated allografts used for the reconstruction of bone defects in 20 knees. They were subdivided into bulk grafts, cortical strut grafts, and morsellised bone. The average follow-up was 4.2 years (2 to 7.2). Radiographs showed union of the allograft to the host in all cases. Two allografts later fractured and three knees required further surgery because of infection. The allografts effectively filled large bone defects around the knee, lessening the need for custom-made and constrained prostheses.

Fresh osteochondral allografts were used to repair post-traumatic osteoarticular defects in 92 knees. At the time of grafting, varus or valgus deformities were corrected by upper tibial or supracondylar femoral osteotomies. A survivorship analysis was performed in which failure was defined as the need for a revision operation or the persistence of the pre-operative symptoms. There was a 75% success rate at five years, 64% at ten years and 63% at 14 years. The failure rate was higher for bipolar grafts than for unipolar and the results in patients over the age of 60 years were poor. The outcome did not depend on the sex of the patient and the results of allografts in the medial and lateral compartments of the knee were similar. Careful patient selection, correction of joint malalignment by osteotomy, and rigid fixation of the graft are all mandatory requirements for success. We recommend this method for the treatment of post-traumatic osteochondral defects in the knees of relatively young and active patients.

We report a case of late dissociation of a one-piece metal-backed acetabular component, associated with a prolific soft-tissue reaction to the polyethylene debris. The polyethylene liner was not visible on the radiographs. The metal-backed shell could not be removed because of bone ingrowth. We recommend that modular systems be utilised in cementless arthroplasty of the hip and that radiographic markers be incorporated in the polyethylene of the acetabular cup.

We followed prospectively 69 patients with 78 proximal femoral allografts performed for revision of total hip arthroplasty for an average of 36 months (range 29 to 68). Large fragment proximal femoral allografts and cortical strut allografts were successful in 85%. Grafts smaller than 3 cm in length (calcar grafts) were clinically successful in 81%, but 50% underwent significant radiographic resorption. We conclude that large proximal femoral allografts and cortical strut allografts provide dependable reconstruction of bone stock deficiencies during revision total hip arthroplasty.

We reviewed 40 cementless Porous Coated Anatomic knee replacements in 34 consecutive patients. The average follow-up was 12.9 months (range 6 to 36 months). At review, loose beads were identified in 23 knees, in 11 on the femoral side and in 16 on the tibial side (in five knees on both sides). One loose bead was adjacent to the patella. In four knees there were intra-articular beads. Radiolucent lines at the interface between bone and prosthesis were seen in 19 knees, in six on the femoral side and in 16 on the tibial side (in three knees on both sides). In relation to the tibial component loose beads were associated with a radiolucent line in all except one case. Progressive loosening with an increasing number of loose beads was seen in three knees. At this early stage of follow-up there was no correlation between the clinical results and the presence of loose beads.