Hip abductor tears(AT) have long been under-recognized, under-reported and under-treated. There is a paucity of data on the prevalence, morphology and associated factors. Patients with “rotator cuff tears of the hip” that are recognized and repaired during total hip arthroplasty(THA) report comparable outcomes to patients with intact abductor tendons at THA. The study was a retrospective review of 997 primary THA done by a single surgeon from 2012–2022. Incidental findings of AT identified during the anterolateral approach to the hip were documented with patient name, gender, age and diagnosis. The extent and size of the tears of the Gluteus medius and Minimus were recorded. Xrays and MRI's were collected for the 140 patients who had AT and matched 1:1 with respect to age and gender against 140 patients that had documented good muscle quality and integrity. Radiographic measurements (Neck shaft angle, inter-teardrop distance, Pelvis width, trochanteric width and irregularities, bodyweight moment arm and abductor moment arm) were compared between the 2 groups in an effort to determine if any radiographic feature would predict AT. The prevalence of AT were 14%. Females had statistically more tears than males(18vs10%), while patients over the age of 70y had statistically more tears overall(19,7vs10,4%), but also more Gluteus Medius tears specifically(13,9vs5,3%). Radiographic measurements did not statistically differ between the tear and control group, except for the presence of trochanteric irregularities. MRI's showed that 50% of AT were missed and subsequently identified during surgery. Abductor tears are still underrecognized and undertreated during THA which can results in inferior outcomes. The surgeon should have an high index of suspicion in elderly females with trochanteric irregularities and although an MRI for every patient won't be feasible, one should always be prepared and equipped to repair the abductor tendons during THA

Complete or nearly complete disruption of the attachment of the gluteus is seen in 10–20% of cases at the time of THA. Special attention is needed to identify the lesion at the time of surgery because the avulsion often is visible only after a thickened hypertrophic trochanteric bursa is removed. From 1/1/09 to 12/31/13, 525 primary hip replacements were performed by a single surgeon. After all total hip components were implanted, the greater trochanteric bursa was removed, and the gluteus medius and minimus attachments to the greater trochanter were visualised and palpated. Ninety-five hips (95 patients) were found to have damage to the muscle attachments to bone. Fifty-four hips had mild damage consisting of splits in the tendon, but no frank avulsion of abductor tendon from their bone attachments. None of these cases had severe atrophy of the abductor muscles, but all had partial fatty infiltration. All hips with this mild lesion had repair of the tendons with #5 Ticron sutures to repair the tendon bundles together, and drill holes through bone to anchor the repair to the greater trochanter. Forty-one hips had severe damage with complete or nearly complete avulsion of the gluteus medius and minimus muscles from their attachments to the greater trochanter. Thirty-five of these hips had partial fatty infiltration of the abductor muscles, but all responded to electrical stimulation. The surface of the greater trochanter was denuded of soft tissue with a rongeur, the muscles were repaired with five-seven #5 Ticron mattress sutures passed through drill holes in the greater trochanter, and a gluteus maximus flap was transferred to the posterior third of the greater trochanter and sutured under the vastus lateralis. Six hips had complete detachment of the gluteus medius and minimus muscles, severe atrophy of the muscles, and poor response of the muscles to electrical stimulation. The gluteus medius and minimus muscles were sutured to the greater trochanter, and gluteus maximus flap was transferred as in the group with functioning gluteus medius and minimus muscles. Postoperatively, patients were instructed to protect the hip for 8 weeks, then abductor exercises were started. The normal hips all had negative Trendelenburg tests at 2 and 5 years postoperative with mild lateral hip pain reported by 11 patients at 2 years, and 12 patients at 5 years. In the group of 54 with mild abductor tendon damage that were treated with simple repair, positive Trendelenburg test was found in 5 hips at 2 years and in 8 hips at 5 years. Lateral hip pain was reported in 7 hips at 2 years, and in 22 at 5 years. In the group of 35 hips with severe avulsion but good muscle tissue, who underwent repair with gluteus maximus flap transfer, all had good abduction against gravity and negative Trendelenburg tests at 2 and 5 years postoperative, and none had lateral hip pain. Of the 6 hips with complete avulsion and poor muscle who underwent abductor muscle repair and gluteus maximus flap transfer, all had weak abduction against gravity, mildly positive Trendelenburg sign, and mild lateral hip pain at 2 and 5 years postoperative. Abductor avulsion is uncommon but not rare, and is detected during THA only by direct examination of the tendon and removal of the trochanteric bursa. Simple repair of mild abductor tendon damage did not prevent progressive abductor weakness in some hips; and the increase in number of patients with lateral hip pain from 2 to 5 years suggests progressive deterioration. Augmentation of the repair with a gluteus maximus flap appears to provide a stable reconstruction of the abductor muscles, and seemed to restore abductor function in the hips with functioning muscles

Abductor deficiency commonly contributes to total hip dislocation. Successful treatment of the deficiency can improve function, decrease pain, and decrease reliance on implants to cure recurrent dislocation. The defining physical exam findings are dependence on ambulatory assistive devices, severe limp, positive Trendelenberg sign, and inability to abduct against gravity. Three techniques have been described for chronic abductor discontinuity in which the abductors have retracted or are absent and cannot reach the greater trochanter: Vastus lateralis muscle shift, Achilles tendon allograft, and gluteus maximus muscle transfer. None of the techniques were specifically performed for dislocation. The vastus lateralis shift transfers the entire muscle proximally maintaining the neurovascular bundle. The procedure requires an incision from the hip to the knee, isolation of the neurovascular bundle, and elevation of the muscle from the femur. The authors admitted that the technique is demanding and not easily applicable to many surgeons. Repair with an Achilles allograft requires an identifiable contractile abductor mass. The allograft is looped through the abductors to bridge the gap to the trochanter. Two variations of a gluteus muscle transfer for abductor deficiency after total hip have been described. A portion of the gluteus maximus with its distal fascial portion are transferred to the greater trochanter. As far as dislocation is concerned an advantage of this technique is the use of the posterior maximus flap to fill a posterior and superior capsular defect not addressed with the other techniques. In addition the technique is easy to perform in almost all cases

Purpose. To determine the effect of early recovery with 2 different MIS THA for patients with dysplastic hip because of relatively severe muscle weakness before surgery. Materials & Methods. MIS THA (248 MIS A/L, 96 2-incision) were performed with single surgeon from 2002. Averaged age was 61 years old. Abductor muscle power and VAS score were analyzed preop, 3, 5 7, 14 days, 2, 6 and 12 months after surgery. Patients were prone position and MicroFET machine (HOGGAN Inc. USA) were used for this analysis. All analysis were performed with single observer (physical therapist). Results. Averaged skin to skin surgical time was 62 min. in MIS A/L (A/L), 96 min. in 2-incision (2I). Hospital stay of MIS A/L were averaged 7 days, 10 in 2-incision and all were direct discharge to their home. Abductor muscle power was down in 3 days (2I; 40%, A/L; 65%: p<0.05) because of pain and swelling in both approach. But, better recovery in both group (2I: 58%, A/L; 75% p<0.05)) 5 days after surgery, and 80% in 2I, 90% A/L in 14 days (N/S). Six and 12 months results were higher compared contra-lateral normal side before surgery. VAS score in 14 days was better in 2-incision (14/100) compared to A/L (23/100). Both walking ability in 100meters with T cane, and stair climbing ability was not statistically significant in both groups. Discussion & Conclusion. Muscle sparing MIS A/L approach had better muscle power recovery but less pain in 2-incision in 14 days (compared Hardinge approach recovery were 60% or less). MIS A/L required none fluoroscopy, had shorter surgical time compared to 2-incision, but indication for patients with limited range of motion and severe deformity with dysplasia need to clarify with more surgical cases

Abductor deficiency after THA can result from proximal femoral bone loss, trochanteric avulsion, muscle destruction associated with infection, pseudotumor, ALTR to metal debris, or other causes. Whiteside has described a transfer of the tensor muscle and anterior gluteus maximus to the greater trochanter for treatment of absent abductors after THA. Transposition of the tensor muscle requires raising an anterior soft tissue flap to the lever of the interval between the tensor muscle and sartorius, which is the same interval used in an anterior approach to the hip. The muscle is transected distally and transposed posteriorly to attach to the proximal femur. This can result in soft tissue redundancy between the posterior tensor muscle and anterior gluteus maximus. This interval is separated and the anterior gluteus maximis also attached to the proximal femur. Relatively large unconstrained (36 mm heads) were not found to be effective in controlling dislocation in patients with abductor deficiency. In our practice, 11 patients with abductor deficiency were treated with Whiteside's tensor muscle transfer and an unconstrained large diameter femoral head. The mean pre-operative abductor strength was 2.2 and improved to 3.2 post-operatively. One patient sustained a dislocation four weeks after surgery which was treated with open reduction. All of the other hips have remained stable. The combination of a large head and tensor muscle transposition may be a viable alternative to use of a fully constrained component in patients with deficient abductors after THA

Abductor deficiency after THA can result from proximal femoral bone loss, trochanteric avulsion, muscle destruction associated with infection, pseudotumor, ALTR to metal debris, or other causes. Constrained acetabular components are indicated to control instability after THA with deficient abductors. However, the added implant constraint also results in greater stresses at the modular liner-locking mechanism of the constrained component and bone-implant fixation interface, which can contribute to mechanical failure of the constrained implant or mechanical loosening. Use of large heads has been effective in reducing the rate of dislocation after primary THA. However, relatively large (36mm) heads were not found to be effective in controlling dislocation in patients with abductor deficiency. Dual mobility implants which can provide considerably larger head diameters than 36mm may offer an advantage in improving stability in patients with abductor deficiency. However the utility of these devices in controlling instability after THA with deficient abductors has not been established. Whiteside has described a transfer of the tensor muscle and anterior gluteus maximus to the greater trochanter for treatment of absent abductors after THA. Transposition of the tensor muscle requires raising an anterior soft tissue flap to the lever of the interval between the tensor muscle and sartorius, which is the same interval used in an anterior approach to the hip. The muscle is transected distally and transposed posteriorly to attach to the proximal femur. This can result in soft tissue redundancy between the posterior tensor muscle and anterior gluteus maximus. This interval is separated and the anterior gluteus maximus also attached to the proximal femur. The transposed tensor muscle provides muscle coverage over the greater trochanter, which may be beneficial in controlling lateral hip pain. In our practice, 11 patients were treated with Whiteside's tensor muscle transfer. Six patients had absent abductors, one had an avulsed greater trochanter, and four intact but weak abductors. One patient had a muscle transposition alone, one had an ORIF of the greater trochanter and muscle transposition, two had a muscle transposition and head/liner exchange, three had a muscle transposition and cup revision, two had a femoral revision and liner exchange with muscle transposition, and two had a muscle transposition with both component revision. None of the patients had constrained components. The mean pre-operative abductor strength was 2.2 (0/5 in four patients 3/5 in four patients, and 4/5 in three patients). Pre-operative lateral hip pain was none or mild in two patients, moderate in three, and severe in six patients. Mean post-operative abductor strength was 3.2 (2/5 in four patients, 3/5 in three, 4/5 in two, 5/5 in two patients). Post-operative lateral hip pain was none in five and mild in six patients. One patient sustained a dislocation four weeks after surgery which was treated with open reduction. All of the other hips have remained stable. Treatment of patients with hip instability and abductor deficiency has generally required use of a constrained acetabular component. In our experience, transfer of the tensor muscle and anterior gluteus maximus to the greater trochanter can improve abductor strength by one grade and also reduce lateral hip pain. The combination of a large head and tensor muscle transposition may be a viable alternative to use of a fully constrained component in patients with deficient abductors after THA. However, the need for implant constraint should also be individualised and based on factors such as the viability of the transposed muscle, patient compliance with post-operative activity restrictions, femoral head/neck ratio, and cup position

No animal model currently exists for hip abductor tendon tears. We aimed to 1. Develop a large animal model of delayed abductor tendon repair and 2. To compare the results of acute and delayed tendon repair using this model.

Fourteen adult Romney ewes underwent detachment of gluteus medius tendon using diathermy. The detached tendons were protected using silicone tubing. Relook was performed at six and 16 weeks following detachment, histological analysis of the muscle and tendon were performed. We then attempted repair of the tendon in six animals in the six weeks group and compared the results to four acute repairs (tendon detachment and repair performed at the same time). At 12 weeks, all animals were culled and the tendon–bone block taken for histological and mechanical analysis.

Histology grading using the modified Movin score confirmed similar tendon degenerative changes at both six and 16 weeks following detachment. Biomechanical testing demonstrated inferior mechanical properties in both the 6 and 16 weeks groups compared to healthy controls.

At 12 weeks post repair, the acute repair group had a lower Movin's score (6.9 vs 9.4, p=0.064), and better muscle coverage (79.4% of normal vs 59.8%). On mechanical testing, the acute group had a significantly improved Young's Modulus compared to the delayed repair model (57.5MPa vs 39.4MPa, p=0.032)

A six week delay between detachment and repair is sufficient to produce significant degenerative changes in the gluteus medius tendon. There are significant histological and mechanical differences in the acute and delayed repair groups at 12 weeks post op, suggesting that a delayed repair model should be used to study the clinical problem.

Avulsion of the abductor muscles of the hip may cause severe limp and pain. Limited literature is available on treatment approaches for this problem, and each has shortcomings. This study describes a muscle transfer technique to treat complete irreparable avulsion of the hip abductor muscles and tendons.

Ten adult cadaver specimens were dissected to determine nerve and blood supply point of entry in the gluteus maximus and tensor fascia lata (TFL) and evaluate the feasibility and safety of transferring these muscles to substitute for the gluteus medius and minimus. In this technique, the anterior portion of the gluteus maximus and the entire TFL are mobilised and transferred to the greater trochanter such that the muscle fiber direction of the transferred muscles closely matches that of the gluteus medius and minimus. Five patients (five hips) were treated for primary irreparable disruption of the hip abductor muscles using this technique between January 2008 and April 2011. All patients had severe or moderate pain, severe abductor limp, and positive Trendelenburg sign. Patients were evaluated for pain and function at a mean of 28 months (range, 18–60 months) after surgery.

All patients could actively abduct 3 months post-operatively. At 1 year post-operatively, three patients had no hip pain, two had mild pain that did not limit their activity, three had no limp, and one had mild limp. One patient fell, fractured his greater trochanter, and has persistent limp and abduction weakness.

The anterior portion of the gluteus maximus and the TFL can be transferred to the greater trochanter to substitute for abductor deficiency. In this small series, the surgical procedure was reproducible and effective; further studies with more patients and longer follow-up are needed to confirm this.

Hip abductor deficiency (HAD) associated with hip arthroplasty can be a chronic, painful condition that can lead to abnormalities in gait and instability of the hip. HAD is often confused with trochanteric bursitis and patients are often delayed in diagnosis after protracted courses of therapy and steroid injection. A high index of suspicion is subsequently warranted.

Risk factors for HAD include female gender, older age, and surgical approach. The Hardinge approach is most commonly associated with HAD because of failure of repair at the time of index surgery or subsequent late degenerative or traumatic rupture. Injury to the superior gluteal nerve at exposure can also result in HAD and is more commonly associated with anterolateral approaches. Multiple surgeries, chronic infection, and chronic inflammation from osteolysis or metal debris are also risk factors especially as they can result in bone stock deficiency and direct injury to muscle. Increased offset and/or leg length can also contribute to HAD, especially when both are present.

Physical exam demonstrates abductor weakness with walking and single leg stance. There is often a palpable defect over the greater trochanter and palpation in that area usually elicits significant focal pain. Note may be made of multiple incisions. Increased leg length may be seen.

Radiographs may demonstrate avulsion of the greater trochanter or significant osteolysis. Significant polyethylene wear or a metal-on-metal implant should be considered as risk factors, as well as the presence of increased offset and/or leg length. Ultrasound or MRI are helpful in confirming the diagnosis but false negatives and positive results are possible.

Treatment is difficult, especially since most patients have failed conservative management before diagnosis of HAD is made. Surgical options include allograft and mesh reconstruction as well as autologous muscle transfers. Modest to good results have been reported, but reproducibility is challenging. In the case of increased offset and leg length, revision of the components to reduce offset and leg length may be considered. In the case of significant instability, abductor repair may require constrained or multi-polar liners to augment the surgical repair.

HAD is a chronic problem that is difficult to diagnose and treat. Detailed informed consent appropriately setting patient expectations with a comprehensive surgical plan is required if surgery is to be considered. Be judicious when offering this surgery.

We have looked at a single surgeons results for hip abductor repair in a population of patients and assessed them pre and post operatively.

We collected data over a 2 year period and each patient underwent a telephone consultation and were scored both pre operatively and post operatively using the non-arthritic hip score (NAHS) and UCLA activity score (UCLA).

A total of 15 patients were included in the study over a 2 year period. 93% underwent some form of investigation prior to surgery. Intra-operatively all patients were found to have pathological abductors. 9 patients were found to have partial avulsions of the abductors and the other 6 had under surface tears or detachments. The mean preoperative NAHS was 35.7/80 and >3/12 post operatively was 68.8/80 (p value <0.001). The mean preoperative UCLA score was 3.1/10 and >3/12 post operatively was 6.6/10 (p value <0.001).

There is a statistically significant improvement in the NAHS of these patients as early as 3/12 and therefore early exploration is advised by the team. Surgical exploration is advised if the patient remains symptomatic despite having negative imaging results as this condition continues to go untreated despite the patients having a significant improvement post operatively.

Loss of the abductor portions of the gluteus medius and gluteus minimus muscles due to total hip arthroplasty (THA) causes severe limp and often instability. To minimise the risk of limp and instability the anterior half of the gluteus maximus was transferred to the greater trochanter and sutured under the vastus lateralis. A separate posterior flap was transferred under the primary flap to substitute for the gluteus minimus and capsule. To ensure tight repair, the flaps were attached and tensioned in abduction.

The technique was performed in 11 patients (11 hips) with complete loss of abductor attachment; the procedure was performed in 9 patients during THA and in 2 later as a secondary procedure. Pre-operatively, all patients had abductor lurch, positive Trendelenburg sign, and no abduction of the hip against gravity. The follow up ranged from 16 to 42 months.

Post-operatively, 9 patients had strong abduction of the hip against gravity, no abductor lurch, and negative Trendelenburg sign. One patient had weak abduction against gravity, negative Trendelenburg sign, and slight abductor lurch. One patient failed to achieve strong abduction, had severe limp after 6 months of protection and physical therapy, and was lost to follow up.

Gluteus maximus transfer can restore abductor function in THA, but it is technically demanding and requires careful, prolonged rehabilitation.

Management of recurrent instability of the hip requires careful assessment to determine any identifiable causative factors. While plain radiographs can give a general impression, CT is the best methodology for objective measurement. Variables that can be measured include: prosthetic femoral anteversion, comparison to contralateral native femoral anteversion, total offset from the medial wall of the pelvis to the lateral side of the greater trochanter, comparison to total offset on the contralateral side, acetabular inclination, & acetabular anteversion. Wera et al describe potential causes of instability. These are typed into I. Acetabular Component Malposition; II. Femoral Component Malposition; III. Abductor Deficiency; IV. Impingement; V. Late Wear; and VI. Unknown. Acetabular component malposition is the most common cause of instability and so measurement of cup orientation is essential. It is well known that excessive or inadequate anteversion can lead to anterior and posterior dislocation respectively but horizontal components are also associated with posterior dislocation due to deficient posterior/inferior acetabular surface. Similarly, excessive or inadequate femoral anteversion can be easily identified on CT as can insufficient total offset of the reconstructed joint compared to the contralateral side. This can be caused by medialization of the acetabular component. Abductor deficiency can be a soft-tissue cause of instability, but it certainly isn't the only one. Knowledge of the prior surgical exposure can be instructive. Anterior exposures can be prone to deficient anterior capsule just as posterior exposures can be prone to deficient posterior capsule and short rotators, while anterolateral and lateral exposures can be associated with gluteus minimus and gluteus medius compromise. Impingement, whether involving implants, bone, or soft tissue are primarily secondary to the above factors, if osteophytes were properly trimmed at the index procedure. Correction of the incorrect variables is the primary goal of revision for instability and greatly preferable to using salvage options such as dual-mobility or constrained articulations which invoke additional concerns. Ultimately though, such salvage options are necessary if the cause of the instability cannot be determined or can be determined but not corrected. Bracing, while highly inconvenient and sometimes impractical for certain patients, still has a role in specific circumstances. Formal analysis of the unstable prosthetic reconstruction is the key to successful treatment

Thumb Carpometacarpal (CMC) arthritis is a common pathology of the hand. Surgical treatment with thumb reconstruction is well described. Retrospective outcomes have been described for multiple techniques, suggesting patient satisfaction with multiple different techniques. The Thompson technique uses a slip of Abductor Pollicis Longus for suspension and interposition as well as excision of the trapezium. Retrospective outcomes suggest good patient satisfaction. We describe the improvement in Patient rated outcomes scores (PROS) and changes in pinch and grip strength in a prospectively collected cohort of patients treated with a modification of the Thompson technique. To assess changes in Patient-Rated Wrist Evaluation (PRWE) and Disabilities of the Arm, Shoulder, and Hand (QDASH) scores, as well as to determine the percentage of patients that surpassed the Minimal Clinically Important Difference (MCID) figure that has been described in the literature for these tests. In addition, measurements for evaluation of pinch and grip strength prior to surgery, at six, and at twelve months follow-up were done. Between June 2016 and February 2019, a consecutive prospective series of Thirty-seven LRTI procedures with APL suspension arthroplasty (Thompson technique) were performed on 34 patients with osteoarthritis of the thumb CMC joint (24 women / 13 men; age 63±8.553). All surgeries were performed by the senior surgeon. Data was collected as part of a wrist pain database. Patients failing conservative treatment and electing surgical management of thumb arthritis were enrolled into the database. Patients were evaluated pre-operatively with the PRWE and QDASH questionnaires and grip and pinch strength measurements, and postoperatively at 6 and 12 months. The MCID for QDASH and PRWE is 14 and will be evaluated at the same time points for each patient. Paired student T-test was used to determine differences in the means. Data are presented as mean ± SD unless stated otherwise. Differences with p<.05 were considered significant. Compared to the pre-operative assessment, at six months, the means of PRWE pain score and PRWE functional score decreased significantly (32.824 SD±10.721 vs. 19.265 SD±12.268 and 30.262 SD±10.050 vs. 16.431 SD± 9.697 respectively, n=34,, p<0.05). 69% of the patients surpassed the MCID of 14 six months after the surgery. In addition, QDASH mean score also dropped from 56.108 to 32.219 (SD± 21.375 n=32. p<0.05) at six months. At one year, 76% of the patients were above the MCID of 14. The mean scores of these three questionnaires did not show significant change between six and twelve months. Compared to the initial pre-operative assessment, we found no statistically significant difference in the means of grip strength, point pinch, and lateral key pinch at six and twelve months. Thumb reconstruction with APL suspension arthroplasty demonstrates significant improvement in pain and functionality. No significant improvement in grip and pinch strength is observed, even at one year postoperatively

The main challenges in hip arthrodesis takedown include the decision to perform fusion takedown and the technical difficulties of doing so. In addition to the functional disadvantages of hip fusion, the long-term effects of hip arthrodesis include low back pain and in some cases ipsilateral knee pain. Indications for fusion conversion to THA include arthrodesis malposition, pseudoarthrosis, and ipsilateral knee, low back, contralateral hip problems, and functional disadvantages of ipsilateral hip fusion. When deciding whether or not to take down fusion, consider the severity of the current problem, risks of takedown and likely benefits of takedown. Best results of fusion takedown occur if abductor function is likely to be present. If the abductors are not likely to function well, dearthrodesis may still help, but the patient will have a profound Trendelenburg or Duchenne gait and risk of hip instability will be higher. Abductor assessment can be performed by determining if the abductors contract on physical exam and determining if the previous form of fusion spared the abductors and greater trochanter. EMG and MRI also can be performed to assess the abductors, but value in this setting is unproven. Before dearthrodesis establish realistic expectations: most patients will gain hip motion—but not normal motion, most will see improvement in back/knee pain, but many will become cane-dependent for life. The main technical issues to overcome involve exposure, femoral neck osteotomy, acetabular preparation, and femoral fixation. Exposure can be conventional posterior, anterolateral or direct anterior with an in-situ femoral neck cut. In complex cases, a transtrochanteric approach is often helpful. The in-situ neck cut is facilitated by fluoroscopy or intraoperative radiograph to make sure the cut is at the correct level and at the correct angle. Be careful not to angle into the pelvis with the cut. Acetabular preparation is more complex because anatomic landmarks often are absent or distorted. Try to find landmarks including ischium, ilium, teardrop, and fovea. Confirm location with fluoroscopy as reaming commences and during reaming. Depth of reaming can be improved by using the fovea (if present) and teardrop on fluoroscopy. Cup fixation is usually an uncemented cup, fixed with multiple screws because bone quality typically is compromised. Femoral fixation is at the surgeon's discretion, recognizing the proximal bone may be distorted in some cases. Postoperative management includes protected weight bearing as needed and heterotopic bone prophylaxis in selected patients

Recurrent dislocation following total hip arthroplasty (THA) is a complex, multifactorial problem that has been shown to be the most common indication for revision THA. At our center, we have tried to approach the unstable hip by identifying the primary cause of instability and correcting that at the time of revision surgery. Type 1:. Malposition of the acetabular component treated with revision of the acetabular component and upsizing the femoral head. Type 2:. Malposition of the femoral component treated with revision of the femur and upsizing the femoral head. Type 3:. Abductor deficiency treated with a constrained liner or dual mobility bearing. Type 4:. Soft tissue or bony impingement treated with removal of impingement sources and upsizing the femoral head. Type 5:. Late wear of the bearing treated with bearing surface exchange and upsizing the femoral head. Type 6:. Unclear etiology treated with a constrained liner or dual mobility articulation. These may be patients with abnormal spino-pelvic motion. The most common etiologies of instability in our experience include cup malposition (Type 1) and abductor deficiency (Type 3). We reviewed 75 hips revised for instability and at a mean 35.3 months 11 re-dislocations occurred (14.6%). Acetabular revisions were protective against re-dislocation (p<0.02). The number of previous operations (p=0.04) and previously failed constrained liners (p<0.02) were risk factors for failure. The highest risk of failure was in patients with abductor insufficiency with revisions for other etiologies having a success rate of 90%. Although instability can be multifactorial, by identifying the primary cause of instability, a rational approach to treatment can be formulated. In general the poorest results were seen in patients with abductor deficiency. Given the high rate of failure of constrained liners (9 of the 11 failures were constrained), we currently are exploring alternatives such as dual mobility articulations. Our early experience with dual mobility suggests improved results when compared to constrained liners

Recurrent dislocation following total hip arthroplasty (THA) is a complex, multifactorial problem that has been shown to be the most common indication for revision THA. At our center, we have tried to approach the unstable hip by identifying the primary cause of instability and correcting that at the time of revision surgery. Type 1: Malposition of the acetabular component treated with revision of the acetabular component and upsizing the femoral head. Type 2: Malposition of the femoral component treated with revision of the femur and upsizing the femoral head. Type 3: Abductor deficiency treated with a constrained liner or dual mobility bearing. Type 4: Soft tissue or bony impingement treated with removal of impingement sources and upsizing the femoral head. Type 5: Late wear of the bearing treated with bearing surface exchange and upsizing the femoral head. Type 6: Unclear etiology treated with a constrained liner or dual mobility articulation. The most common etiologies of instability in our experience include cup malposition (Type 1) and abductor deficiency (Type 3). We reviewed 75 hips revised for instability and at a mean 35.3 months, 11 re-dislocations occurred (14.6%). Acetabular revisions were protective against re-dislocation (p<0.02). The number of previous operations (p=0.04) and previously failed constrained liners (p<0.02) were risk factors for failure. The highest risk of failure was in patients with abductor insufficiency with revisions for other etiologies having a success rate of 90%. Although instability can be multifactorial, by identifying the primary cause of instability, a rational approach to treatment can be formulated. In general, the poorest results were seen in patients with abductor deficiency. Given the high rate of failure of constrained liners (9 of the 11 failures were constrained), we currently are exploring alternatives such as dual mobility articulations. Our early experience with dual mobility suggests improved results when compared to constrained liners

Introduction. Implantation of total hip replacement (THR) remains a concern in patients with developmental dysplasia of the hip (DDH) because of bone deformities and previous surgeries. In this frequently young population, anatomical reconstruction of the hip rotation centre is particularly challenging in severe, low and high dislocation, DDH. The basic principles of the technique and the implant selection may affect the long-term results. The aim of the study was to compare surgical difficulties and outcome in patients who underwent THR due to arthritis secondary to moderate or severe DDH. Material and Methods. We assessed 131 hips in patients with moderate DDH (group 1) and 56 with severe DDH (Group 2) who underwent an alumina-on-alumina THR between 1999 and 2012. The mean follow-up was 11.3 years (range, 5 to 18). Mean age was 51.4 years in group 1 and 42.2 in group 2. There were previous surgery in 5 hips in group 1 and in 20 in group 2 (p<0.001). A dysplastic acetabular shape type C according to Dorr and a radiological cylindrical femur were both more frequent in group 2 (in both cases p<0.001). We always tried to place the acetabular component in the true acetabulum. Smaller cups (p<0.001), screw use for primary fixation (p<0.001) and bone autograft used as segmental reinforcement in cases of roof deficiency (p<0.001) were more frequent in group 2. Radiological analysis of the cup included acetabular abduction, version and Wiberg angles, horizontal, vertical, and hip rotation centre distances, and acetabular head index. Abductor mechanism reconstruction according to the lever arm distance and height of the greater trochanter was also evaluated. Cup placement within or outside Lewinnek´s safe zone was recorded. Two-way ANOVA with repeated measures were used to analyse clinical and radiological changes. Results. There were 6 cups revised for aseptic loosening, three in each group. Survivorship analysis at 15 years: 97.3% (95% IC 94.4–100) for group 1 and 93.0% (95% IC 85.2–100) for group 2 (p=0.186). Despite a worse preoperative status in group 2, the outcome improved similarly in both groups. Postoperative radiological measurements were better in group 1 except for acetabular acetabular and version angles. The improvement from the pre- to the post-operative situation was greater in group 2 except for the height of the greater trochanter. Acetabular component placement within the Lewinnek´s safe zone was similar in both groups. All revised cups were outside this zone. No osteolysis or complications related to the use of ceramics were found. Conclusions. The alumina-on-alumina THR provided good results in both groups including pain relief and functional improvement. Placing the acetabular component in the true acetabulum inside the Lewinnek safe zone can ensure a good result in these challenging dysplastic hips

Recurrent dislocation following total hip arthroplasty (THA) is a complex, multifactorial problem that has been shown to be the most common indication for revision THA. At our center, we have tried to approach the unstable hip by identifying the primary cause of instability and correcting that at the time of revision surgery. Type 1: Malposition of the acetabular component treated with revision of the acetabular component and upsizing the femoral head. Type 2: Malposition of the femoral component treated with revision of the femur and upsizing the femoral head. Type 3: Abductor deficiency treated with a constrained liner or dual mobility bearing. Type 4: Soft tissue or bony impingement treated with removal of impingement sources and upsizing the femoral head. Type 5: Late wear of the bearing treated with bearing surface exchange and upsizing the femoral head. Type 6: Unclear etiology treated with a constrained liner or dual mobility articulation. The most common etiologies of instability in our experience include cup malposition (Type 1) and abductor deficiency (Type 3). We reviewed 75 hips revised for instability and at a mean 35.3 months 11 re-dislocations occurred (14.6%). Acetabular revisions were protective against re-dislocation (p<0.015). The number of previous operations (p=0.0379) and previously failed constrained liners (p<0.02) were risk factors for failure. The highest risk of failure was in patients with abductor insufficiency with revisions for other etiologies having a success rate of 90%. Although instability can be multifactorial, by identifying the primary cause of instability, a rational approach to treatment can be formulated. In general the poorest results were seen in patients with abductor deficiency. Given the high rate of failure of constrained liners (9 of the 11 failures were constrained), we currently are exploring alternatives such as dual mobility articulations

The main challenges in hip arthrodesis takedown include the decision to perform fusion takedown and the technical difficulties of doing so. In addition to the functional disadvantages of hip fusion, the long-term effects of hip arthrodesis include low back pain and in some cases ipsilateral knee pain. Indications for fusion conversion to THA include arthrodesis malposition, pseudoarthrosis, and ipsilateral knee, low back, contralateral hip problems, and functional disadvantages of ipsilateral hip fusion. When deciding whether or not to take down a fusion, consider the severity of the current problem, risks of takedown and likely benefits of takedown. Best results of fusion takedown occur if abductor function is likely to be present. If the abductors are not likely to function well, dearthrodesis may still help, but the patient will have a profound Trendelenburg or Duchenne gait and risk of hip instability will be higher. Abductor assessment can be performed by determining if the abductors contract on physical exam and determining if the previous form of fusion spared the abductors and greater trochanter. EMG and MRI also can be performed to assess the abductors, but value in this setting is unproven. Before dearthrodesis establish realistic expectations: most patients will gain hip motion—but not normal motion, most will see improvement in back/knee pain, but many will become cane-dependent for life. The main technical issues to overcome involve exposure, femoral neck osteotomy, acetabular preparation, and femoral fixation. Exposure can be conventional posterior, anterolateral or direct anterior with an in situ femoral neck cut. In complex cases, a transtrochanteric approach is often helpful. The in situ neck cut is facilitated by fluoroscopy or intra-operative radiograph to make sure the cut is at the correct level and at the correct angle. Be careful not to angle into the pelvis with the cut. Acetabular preparation is more complex because anatomic landmarks often are absent or distorted. Try to find landmarks including ischium, ilium, teardrop, and fovea. Confirm location with fluoroscopy as reaming commences and during reaming. Depth of reaming can be improved by using the fovea (if present) and teardrop on fluoroscopy. Cup fixation is usually an uncemented cup, fixed with multiple screws because bone quality typically is compromised. Femoral fixation is at the surgeon's discretion, recognizing the proximal bone may be distorted in some cases. Post-operative management includes protected weight bearing as needed and heterotopic bone prophylaxis in selected patients

Introduction. Failed operated intertrochanteric fractures (with screw cutout, joint penetration, varus collapse, nonunion, or femoral head avascular necrosis) pose treatment dilemmas. The ideal approach is re-osteosynthesis with autologous bone grafting. When the femoral head is unsalvageable, conversion to a prosthetic hip replacement is necessary. Materials/Methods. Thirty-seven patients with failed dynamic hip screw fixation (and unsalvageable femoral heads) were treated with cementless hip arthroplasty (13 underwent Bipolar Arthroplasty, 24 had Total Hip Arthroplasty) over a 5-year period (Dec 2005 to Nov 2010). Seven needed a modified trochanteric split, and the rest were managed by standard anterolateral approach. Abductor mechanism was reconstructed using strong nonabsorbable sutures (ethibond 5) or stainless steel wires. The calcar was partially reconstructed using remnant femoral head and cerclage wiring in a few cases. Results. Clinico-radiological assessment was done at three, six, 12 months and yearly thereafter over an average 36 months (range, three to 60 months). Stem loosening, lysis, subsidence and trochanteric union were studied. At last follow-up, one patient had died, and there were two instances each of stem subsidence and trochanteric nonunion. Clinical results using Harris hip scores were good or excellent. Conclusion. Management of nonsalvageable femoral heads after failed intertrochanteric fracture fixation is possible with cementless hip arthroplasty. Successful outcomes depend on functional abductor reconstruction, fracture and femoral shaft penetration prevention. Autograft, allograft or head/neck replacement components are necessary sometimes