OBJECTIVE

To examine the short term patient assessed functional results of the Journey BCS ¯(Smith & Nephew) and Triathlon ¯(Stryker Orthopaedics, Mahwah, NJ) total knee replacements when compared to the Scorpio ¯(Stryker) total knee replacement using a multi-surgeon case control design in a single centre.

Improved surgical techniques and new fixation methods have revived interest in high tibial osteotomy surgery in recent years. Our aim was to review our first 59 cases. All patients underwent radiological and clinical review including pre and post operative scores.

Mean age at surgery was 43 (22-59) and mean follow up is 22 months.

The mean pre-operative limb alignment was 5.4° varus (range 1°-16°) with correction to 2° valgus (range -1° - 7°).

HTO is known to increase tibial slope and in this series the change in tibial slope from -5.2° (95%CI: -6.36 to -4.07)) to -7.8° (-8.83 to –6.89) was statistically significant. p= 0.0014 (Mann Whitney).

Patellar height is often reduced following opening wedge HTO and this is confirmed in our series. The Blackburne-Peel ratio changed from 0.74 to 0.58 and the Caton-Descamps from 0.83 to 0.7. Both were statistically significant at p<0.0001 and p=0.0001 respectively.

All scores improved post operatively, the knee injury and osteoarthritis outcome (KOOS) from 48 (8-91) to 73 (27-96), the Oxford knee score (OKS) from 25 (3-47) to 37 (9-48), and the EQ5D from 189809 (11221-32333) to 14138 (11111-22233) with the EQ5D VAS improving from 58 to 75. There was no correlation between change in limb alignment, tibial slope or patellar height and any of the scores used.

There were three superficial wound infections, and one non union which was treated with grafting and re fixation. Six patients have had their plate removed.

Improvement in clinical scores in these patients confirms that medial opening wedge HTO is a reliable joint preserving procedure in the short term and our surgical technique is reproducible and consistent with other published series.

It is established good practice that joint replacements should have regular follow-up and for the past seven years at the North Hampshire Hospital a local joint register has been used for this purpose and we compare this with results of the Swedish and UK national registries.

Since March 1999, all primary and revision knee arthroplasties performed at North Hampshire Hospital, Basingstoke have been prospectively recorded onto a database set up by one of the senior authors (JMB). Data from patients entered in the first six years of the register were analysed. All patients have at least one year clinical and radiological review then a minimum of yearly postal follow-up.

As of 31/12/2006, 2854 knee replacement procedures had been performed under the care of 13 consultants. OA was the most common diagnosis in over 75% of knees. 5.2% of patients had died and 4.6% were lost to follow-up. Our revision burden was 3.5% and we had a revision rate of 1.4% for primary total knee replacements. Audit of data for revisions and patello-femoral replacements has enabled us to change our practices. Mean length of stay was 7.2 days for primary total knee arthroplasty versus 4.0 days for unicompartmental knee arthroplasty and 5.4 days for patellofemoral replacement and mean flexion at discharge was 88.4, 93.7 and 88.7 degrees respectively. WOMAC and Oxford scores at 2 years had improved from a mean of 52 and 21 pre-operatively to 74 and 39 respectively for primary total knee arthroplasty. Our costs are estimated at approximately £35 per patient for their lifetime on the register.

Compared to other registries:

Our dataset is more complete and comprehensive

To establish the efficacy of a new arthroscopic technique, for the treatment of stiffness after TKR.

Introduction: The usual surgical procedure for stiffness after a total knee replacement is an open arthrolysis, though an arthroscopic procedure can be considered within six months of the index surgery. We have evolved a new procedure of capsulectomy and anterior release which can be used at any time after TKR in patients with a reduced range of movement (ROM).

Methods: 22 patients (10 women and 12 men) underwent arthroscopic capsulectomy and anterior release for the treatment of loss of movement after TKR. The mean age was 62 (range 47–71 yrs). Mean time between TKR and arthrolysis was 27 months (range 3–54). Indication for the arthroscopic procedure was decreased ROM following TKR. Arthroscopy was performed using anteromedial and anterolateral portals. The dense scar tissue was divided and completely excised arthroscopically. ROM was assessed pre-operatively, immediately post-operatively and at 2, 6, 12 weeks, 6 months and 1 year. The Oxford Knee Score (OKS) and American Knee Society Score (AKSS) were used pre-operatively and at 6 months and 1 year post-operatively.

Results: Pre-operatively mean flexion was 50 degrees (Range 20–90°). Post-operatively it was 94.5° (Range 55–125°). At 1 year this was maintained. The mean OKS pre-operatively was 18.4 (range 8–39). At 1 year it was 29.8 (range 9–39). The AKSS (knee and functional components) showed a similar improvement. The mean knee score increased from 47.3 pre-operatively to 71.6 at 1 year. The functional score rose from a mean of 51.3 pre-operatively to 76.9 at 1 year.

Conclusions: Our technique of arthroscopic capsulectomy and anterior release for the treatment of stiffness following TKR is both successful and safe. At 1 year post-operatively the patients have maintained an increased ROM and significantly improved Oxford and American Knee Society Scores.

We sought to determine whether smoking affected the outcome of reconstruction of the anterior cruciate ligament. We analysed the results of 66 smokers (group 1 with a mean follow-up of 5.67 years (1.1 to 12.7)) and 238 non-smokers (group 2 with a mean follow-up of 6.61 years (1.2 to 11.5)), who were statistically similar in age, gender, graft type, fixation and associated meniscal and chondral pathology. The assessment was performed using the International Knee Documentation Committee form and serial cruciometer readings.

Poor outcomes were reported in group 1 for the mean subjective International Knee Documentation Committee score (p < 0.001), the frequency (p = 0.005) and intensity (p = 0.005) of pain, a side-to-side difference in knee laxity (p = 0.001) and the use of a four-strand hamstring graft (p = 0.015). Patients in group 1 were also less likely to return to their original level of pre-injury sport (p = 0.003) and had an overall worse final 7 International Knee Documentation Committee grade score (p = 0.007).

Despite the well-known negative effects of smoking on tissue healing, the association with an inferior outcome after reconstruction of the anterior cruciate ligament has not previously been described and should be included in the pre-operative counselling of patients undergoing the procedure.

The options for treatment of the young active patient with isolated symptomatic osteoarthritis of the medial compartment and pre-existing deficiency of the anterior cruciate ligament are limited. The potential longevity of the implant and levels of activity of the patient may preclude total knee replacement, and tibial osteotomy and unicompartmental knee arthroplasty are unreliable because of the ligamentous instability. Unicompartmental knee arthroplasties tend to fail because of wear or tibial loosening resulting from eccentric loading. Therefore, we combined reconstruction of the anterior cruciate ligament with unicompartmental arthroplasty of the knee in 15 patients (ACLR group), and matched them with 15 patients who had undergone Oxford unicompartmental knee arthroplasty with an intact anterior cruciate ligament (ACLI group). The clinical and radiological data at a minimum of 2.5 years were compared for both groups.

The groups were well matched for age, gender and length of follow-up and had no significant differences in their pre-operative scores. At the last follow-up, the mean outcome scores for both the ACLR and ACLI groups were high (Oxford knee scores of 46 (37 to 48) and 43 (38 to 46), respectively, objective Knee Society scores of 99 (95 to 100) and 94 (82 to 100), and functional Knee Society scores of 96 and 96 (both 85 to 100). One patient in the ACLR group needed revision to a total knee replacement because of infection. No patient in either group had radiological evidence of component loosening. The radiological study showed no difference in the pattern of tibial loading between the groups.

The short-term clinical results of combined anterior cruciate ligament reconstruction and unicompartmental knee arthroplasty are excellent. The previous shortcomings of unicompartmental knee arthroplasty in the presence of deficiency of the anterior cruciate ligament appear to have been addressed with the combined procedure. This operation seems to be a viable treatment option for young active patients with symptomatic arthritis of the medial compartment, in whom the anterior cruciate ligament has been ruptured.

Abnormal sagittal kinematics after total knee replacement (TKR) can adversely affect functional outcome. Two important determinants of knee kinematics are component geometry and the presence or absence of a posterior-stabilising mechanism (cam-post). We investigated the influence of these variables by comparing the kinematics of a TKR with a polyradial femur with a single radius design, both with and without a cam-post mechanism.

We assessed 55 patients, subdivided into four groups, who had undergone a TKR one year earlier by using an established fluoroscopy protocol in order to examine their kinematics in vivo. The kinematic profile was obtained by measuring the patellar tendon angle through the functional knee flexion range (0° to 90°) and the results compared with 14 normal knees. All designs of TKR had abnormal sagittal kinematics compared with the normal knee. There was a significant (p < 0.05) difference between those of the two TKRs near to full extension. The presence of the cam-post mechanism did not influence the kinematics for either TKR design. These differences suggest that surface geometry is a stronger determinant of kinematics than the presence or absence of a cam-post mechanism for these two designs. This may be because the cam-post mechanism is ineffective.

The tensile strength of the medial patellofemoral ligament (MPFL), and of surgical procedures which reconstitute it, are unknown. Ten fresh cadaver knees were prepared by isolating the patella, leaving only the MPFL as its attachment to the medial femoral condyle. The MPFL was either repaired by using a Kessler suture or reconstructed using either bone anchors or one of two tendon grafting techniques. The tensile strength and the displacement to peak force of the MPFL were then measured using an Instron materials-testing machine.

The MPFL was found to have a mean tensile strength of 208 N (SD 90) at 26 mm (SD 7) of displacement. The strengths of the other techniques were: sutures alone, 37 N (SD 27); bone anchors plus sutures, 142 N (SD 39); blind-tunnel tendon graft, 126 N (SD 21); and through-tunnel tendon graft, 195 N (SD 66). The last was not significantly weaker than the MPFL itself.

Chronic medial collateral ligament (MCL) instability is an unusual clinical problem. Due to the unsatisfactory results of advancement procedures or reconstruction using autologous techniques we have devised a new technique using a non-irradiated tendo achilles allograft construct.

Three patients are presented who had symptomatic MCL insufficiency. The laxity was demonstrated clinically (all grade 3) and radiologically using valgus stress views.

The tendo achilles was fashioned into a triangular composite graft consisting of a bone plug (30 x 10 mm) and the tendon. The bone plug was attached to the femur at the anatomical insertion of the MCL using an interference screw and the tendon on the tibia using a multiple suture anchor technique.

The rehabilitation programme consisted of immediate mobilisation and the use of a brace for twelve weeks.

At follow-up (average 12 months) all patients were asymptomatic, had a full range of movements, no increased clinical laxity and no increased radiological laxity to a valgus force at 25 degrees of flexion when compared to the other side.

We conclude that this is an effective technique in the treatment of chronic symptomatic MCL laxity.

We investigated the implant-bone interface around one design of femoral stem, proximally coated with either a plasma-sprayed porous coating (plain porous) or a hydroxyapatite porous coating (porous HA), or which had been grit-blasted (Interlok). Of 165 patients implanted with a Bimetric hip hemiarthroplasty (Biomet, Bridgend, UK) specimens were retrieved from 58 at post-mortem.

We estimated ingrowth and attachment of bone to the surface of the implant in 21 of these, eight plain porous, seven porous HA and six Interlok, using image analysis and light morphometric techniques. The amount of HA coating was also quantified.

There was significantly more ingrowth (p = 0.012) and attachment of bone (p > 0.05) to the porous HA surface (mean bone ingrowth 29.093 ± 2.019%; mean bone attachment 37.287 ± 2.489%) than to the plain porous surface (mean bone ingrowth 21.762 ± 2.068%; mean bone attachment 18.9411 ± 1.971%). There was no significant difference in attachment between the plain porous and Interlok surfaces. Bone grew more evenly over the surface of the HA coating whereas on the porous surface, bone ingrowth and attachment occurred more on the distal and medial parts of the coated surface. No significant differences in the volume of HA were found with the passage of time.

This study shows that HA coating increases the amount of ingrowth and attachment of bone and leads to a more even distribution of bone over the surface of the implant. This may have implications in reducing stress shielding and limiting osteolysis induced by wear particles.