In 11 paediatric patients (seven girls and four boys, from 12 to 15 years old) with unilateral obligatory patellar dislocation and ligamentous laxity vastus medialis advancement, lateral release, partial patellar ligament transposition and Galeazzi semitendinosus tenodesis was undertaken to stabilise the patella. The diagnostic criterion for ligamentous laxity was based on the Beighton scale. Outcomes were evaluated radiologically and functionally by measurement of the range of knee movement and isokinetic testing. The evaluation also included the Lysholm knee scale. Follow-up studies took place at a mean of 8.1 years (5 to 15) post-operatively.

Normal patellar tracking without any recurrence of dislocation was obtained in ten out of 11 patients. Pain related to vigorous activity was reported by nine patients. Compared with the opposite normal side, the isokinetic tests revealed a statistically significant decrease in the maximal torque values for the affected quadriceps muscle (p = 0.003 and p = 0.004), but no difference between the knee flexors (for angular velocities of 60°/s and 180°/s) (p = 0.858 and p = 0.79).

The applied surgical technique generally prevents the recurrence of the disorder in children with habitual patellar dislocation and ligamentous laxity. Quadriceps muscle weakness can be expected to occur post-operatively,

Cite this article: Bone Joint J 2015;96-B:129–33.

The management of failed autologous chondrocyte implantation (ACI) and matrix-assisted autologous chondrocyte implantation (MACI) for the treatment of symptomatic osteochondral defects in the knee represents a major challenge. Patients are young, active and usually unsuitable for prosthetic replacement. This study reports the results in patients who underwent revision cartilage transplantation of their original ACI/MACI graft for clinical or graft-related failure. We assessed 22 patients (12 men and 10 women) with a mean age of 37.4 years (18 to 48) at a mean of 5.4 years (1.3 to 10.9). The mean period between primary and revision grafting was 46.1 months (7 to 89). The mean defect size was 446.6 mm² (150 to 875) and they were located on 11 medial and two lateral femoral condyles, eight patellae and one trochlea.

The mean modified Cincinnati knee score improved from 40.5 (16 to 77) pre-operatively to 64.9 (8 to 94) at their most recent review (p < 0.001). The visual analogue pain score improved from 6.1 (3 to 9) to 4.7 (0 to 10) (p = 0.042). A total of 14 patients (63%) reported an ‘excellent’ (n = 6) or ‘good’ (n = 8) clinical outcome, 5 ‘fair’ and one ‘poor’ outcome. Two patients underwent patellofemoral joint replacement. This study demonstrates that revision cartilage transplantation after primary ACI and MACI can yield acceptable functional results and continue to preserve the joint.

Cite this article: Bone Joint J 2014;96-B:54–8.

Objectives

Matrix-assisted autologous chondrocyte transplantation (MACT) has been developed and applied in the clinical practice in the last decade to overcome most of the disadvantages of the first generation procedures. The purpose of this systematic review is to document and analyse the available literature on the results of MACT in the treatment of chondral and osteochondral lesions of the knee.

The October 2012 Knee Roundup. 360. looks at: autologous chondrocytes and chondromalacia patellae; drilling the femoral tunnel at ACL reconstruction; whether we repair the radially torn lateral meniscus; factors associated with patellofemoral pain; mechanoreceptors and the allografted ACL; whether high tibial osteotomy can delay the need for knee replacement; return to sport after ACL reconstruction; tissue-engineered cartilage; and the benefits of yoga

Objectives. To assess the effectiveness of a modified tibial tubercle osteotomy as a treatment for arthroscopically diagnosed chondromalacia patellae. Methods. A total of 47 consecutive patients (51 knees) with arthroscopically proven chondromalacia, who had failed conservative management, underwent a modified Fulkerson tibial tubercle osteotomy. The mean age was 34.4 years (19.6 to 52.2). Pre-operatively, none of the patients exhibited signs of patellar maltracking or instability in association with their anterior knee pain. The minimum follow-up for the study was five years (mean 72.6 months (62 to 118)), with only one patient lost to follow-up. Results. A total of 50 knees were reviewed. At final follow-up, the Kujala knee score improved from 39.2 (12 to 63) pre-operatively to 57.7 (16 to 89) post-operatively (p < 0.001). The visual analogue pain score improved from 7.8 (4 to 10) pre-operatively to 5.0 (0 to 10) post-operatively. Overall patient satisfaction with good or excellent results was 72%. Patients with the lowest pre-operative Kujala score benefitted the most. Older patients benefited less than younger ones. The outcome was independent of the grade of chondromalacia. Six patients required screw removal. There were no major complications. Conclusions. We conclude that this modification of the Fulkerson procedure is a safe and useful operation to treat anterior knee pain in well aligned patellofemoral joints due to chondromalacia patellae in adults, when conservative measures have failed

Background. Autologous chondrocyte implantation (ACI) and mosaicplasty (MP) are two methods of repair of symptomatic articular cartilage defects in the adult knee. This study represents the only long-term comparative clinical trial of the two methods. Methods. A prospective, randomised comparison of the two modalities involving 100 patients with symptomatic articular cartilage lesions was undertaken. Patients were followed for ten years. Pain and function were assessed using the modified Cincinnati score, Bentley Stanmore Functional rating system and visual analogue scores. ‘Failure’ was determined by pain, a poor outcome score and arthroscopic evidence of graft disintegration. Results. Patients had a mean age at index operation of 31. There was a long mean pre-op duration of symptoms of seven years and the defects had an average of 1.5 operations (excluding arthroscopy) to the articular cartilage lesion prior to the cartilage repair surgery. The aetiology of the articular cartilage defects was mainly trauma; some patients had osteochondritis dissecans or chondromalacia patellae. Five patients were lost to follow-up. A total of 23 out of 42 mosaicplasty patients failed, 10 out of 58 ACI patients failed (p<0.001). Most patients did well for the first two years when there was a steep failure of mosaicplasty patients, after which the failure rate was more constant. There was a low steady failure rate of ACI over the 10 years. Older patients treated by ACI did worse than younger patients; age was less of a prognostic indicator in MP. Patients irrespective of gender or aetiology of the defect fared better with ACI than MP. Conclusion. At ten years, patients who underwent cartilage repair using ACI fared significantly better than those who underwent mosaicplasty

Autologous chondrocyte implantation (ACI) and mosaicplasty are methods of treating symptomatic articular cartilage defects in the knee. This study represents the first long-term randomised comparison of the two techniques in 100 patients at a minimum follow-up of ten years. The mean age of the patients at the time of surgery was 31.3 years (16 to 49); the mean duration of symptoms pre-operatively was 7.2 years (9 months to 20 years). The lesions were large with the mean size for the ACI group being 440.9 mm² (100 to 1050) and the mosaicplasty group being 399.6 mm² (100 to 2000). Patients had a mean of 1.5 previous operations (0 to 4) to the articular cartilage defect. Patients were assessed using the modified Cincinnati knee score and the Stanmore-Bentley Functional Rating system. The number of patients whose repair had failed at ten years was ten of 58 (17%) in the ACI group and 23 of 42 (55%) in the mosaicplasty group (p < 0.001).

The functional outcome of those patients with a surviving graft was significantly better in patients who underwent ACI compared with mosaicplasty (p = 0.02).

Matrix-induced autologous chondrocyte implantation (MACI) is an established technique used to treat osteochondral lesions in the knee. For larger osteochondral lesions (> 5 cm²) deeper than approximately 8 mm we have combined the use of two MACI membranes with impaction grafting of the subchondral bone. We report our results of 14 patients who underwent the ‘bilayer collagen membrane’ technique (BCMT) with a mean follow-up of 5.2 years (2 to 8). There were 12 men and two women with a mean age of 23.6 years (16 to 40). The mean size of the defect was 7.2 cm² (5.2 to 12 cm²) and were located on the medial (ten) or lateral (four) femoral condyles. The mean modified Cincinnati knee score improved from 45.1 (22 to 70) pre-operatively to 82.8 (34 to 98) at the most recent review (p < 0.05). The visual analogue pain score improved from 7.3 (4 to 10) to 1.7 (0 to 6) (p < 0.05). Twelve patients were considered to have a good or excellent clinical outcome. One graft failed at six years.

The BCMT resulted in excellent functional results and durable repair of large and deep osteochondral lesions without a high incidence of graft-related complications.

Isolated patellofemoral osteoarthritis can be a disabling disease. When conservative treatment fails, surgical options can be unpredictable and may be considered too aggressive for middle-aged and active people. We analysed the clinical and radiological results of a new coronal osteotomy involving thinning of the patella in a selected group of patients with isolated patellofemoral osteoarthritis. Since 1991, 31 patients (35 knees) have been treated, of whom 34 were available for follow-up at a mean of 9.1 years. The Knee Society Score, the Patellar score and the Short-form-36 questionnaire were used for clinical evaluation. We also examined the radiological features to confirm bone consolidation and assess the progression of osteoarthritis. A significant improvement in the functional scores and radiological parameters was noted. All patients except one were satisfied with the operation. Radiological progression of the patellofemoral osteoarthritis was slowed but radiological femorotibial osteoarthritis progressed in 23 (65%) cases, with a total knee replacement becoming necessary in four cases without technical problems in resurfacing the patella. We compared the results with other forms of surgical treatment reported in the literature.

This treatment offers good clinical and radiological results, presenting an alternative method of managing patellofemoral osteoarthritis.

Many radiographic techniques have been described for measuring patellar height. They can be divided into two groups: those that relate the position of the patella to the femur (direct) and those that relate it to the tibia (indirect). This article looks at the methods that have been described, the logic behind their conception and the critical analyses that have been performed to test them.

Introduction: The indications for patellectomy have been considerably narrowed in recent years, but there remains a cohort of patients with previous patellectomies that remain symptomatic. In addition, these patients can develop osteoarthrosis or instability, and their treatment is challenging. We report our experience of the use of a novel implant to substitute for the absent native patella. Materials and Methods: Six patients were treated with the Augmentation Patella (Zimmer, Allendale, USA), which was sutured to the patellar tendon. All 6 patients had previously had a patellectomy for anterior knee pain syndrome or chondromalacia patellae, between 5 and 22 years previously. They all had an arthroscopy to document the extent of degenerative changes. Patients with trochlear changes only had the trochlea resurfaced (4 cases) and those with tibio-femoral changes as well had a total knee replacement (2 cases). Results: One patient reported excellent relief of pain, with no evidence of radiological loosening. Two patients continued to complain of pain despite the implant being solidly fixed. One patient developed wound complications secondary to difficult closure due to the bulk of the implant. In two patients, the implant loosened within 15 months necessitating further surgery to retrieve the Augmentation Patella. Discussion: The results of the Augmentation Patella in our series of patients with previous patellectomies have been disappointing. Previous studies, where this implant has been used with a remaining shell of patella, has yielded better results. This suggests that bony ingrowth is important for a successful outcome. We recommend that this device should only be implanted if bony contact is possible

Autologous chondrocyte implantation is an option in the treatment of full-thickness chondral or osteochondral injuries which are symptomatic. The goal of surgery and rehabilitation is the replacement of damaged cartilage with hyaline or hyaline-like cartilage, producing improved levels of function and preventing early osteoarthritis. The intermediate results have been promising in terms of functional and clinical improvement.

Our aim was to explore the hypothesis that the histological quality of the repair tissue formed after autologous chondrocyte implantation improved with increasing time after implantation.

In all, 248 patients who had undergone autologous chondrocyte implantation had biopsies taken of the repair tissue which then underwent histological grading. Statistical analysis suggested that with doubling of the time after implantation the likelihood of a favourable histological outcome was increased by more than fourfold (p < 0.001).

Chondral damage to the knee is common and, if left untreated, can proceed to degenerative osteoarthritis. In symptomatic patients established methods of management rely on the formation of fibrocartilage which has poor resistance to shear forces. The formation of hyaline or hyaline-like cartilage may be induced by implanting autologous, cultured chondrocytes into the chondral or osteochondral defect.

Autologous chondrocyte implantation may be used for full-thickness chondral or osteochondral injuries which are painful and debilitating with the aim of replacing damaged cartilage with hyaline or hyaline-like cartilage, leading to improved function. The intermediate and long-term functional and clinical results are promising.

We provide a review of autologous chondrocyte implantation and describe our experience with the technique at our institution with a mean follow-up of 32 months (1 to 9 years).

The procedure is shown to offer statistically significant improvement with advantages over other methods of management of chondral defects.

Introduction and aim: Several authors have suggested that hyaline repair tissue following autologous – chondrocyte implantation (ACI) gives better clinical results than either mixed hyaline and fibrocartilage or fibrocartilage alone. This data is based on the use of periosteum as a covering membrane in these previous studies. We have for some years been using a porcine collagen type 1/III membrane (ACI-C) instead of periosteum and have now the opportunity to analyze the clinical results when compared with the histology of the repaired defect. We have also analysed the influence on the result of age and sex of the patient, the etiology of the lesion, the duration of the knee symptoms, number of previous knee procedures, the site and size of defect and the preoperative functional scores. Method: Until 2004, 234 patients underwent autologous chondrocyte implantation at our centre. The patients were assessed clinically by their modified Cincinnati scores prospectively from 1 to 4 years from surgery. Also at arthroscopy (1 to 3 years following ACI-C) they underwent biopsy of the implant where possible and the neo-cartilage was graded as hyaline (H), mixed fibrohyaline (F.H), fibrocartilagenous (F.C) and fibrous (F). Results: The clinical results showed that older patients had poorer results (p< 0.001) and a high preoperative modified Cincinnati score predicted a good result (p< 0.001). Concerning the cause of the defect, the percentage of patients with excellent and good results were significantly low among those with previously failed ACIs and mosaicplaties (12.5%) compared with those following trauma, osteochondritis dessicans and chondromalacia patellae (67% to 77%). At 4 year follow-up, 75% of patients with hyaline neo-cartilage had excellent and good modified Cincinnati scores whereas those with mixed fibro-hyaline and fibro-cartilage had fewer excellent and good results (44.4% and 54.5% respectively). The other parameters such as gender, the site of defect, duration of knee symptoms and the number of previous procedures and the size of the defect did not significantly influence the outcome. In conclusion, patients most likely to benefit from autologous chondrocyte implantation using a collagen membrane (ACI – C) are younger patients with higher preoperative functional scores and those who develop hyaline neo-cartilage

We assessed the reproducibility and accuracy of four ratios used to measure patellar height, namely the Blackburne-Peel, Caton-Deschamps, Insall-Salvati and modified Insall-Salvati, before and after total knee arthroplasty. The patellar height was measured, by means of the four ratios, on the pre- and post-operative lateral radiographs of 44 patients (45 knees) who had undergone total knee arthroplasty. Two independent observers measured the films sequentially, in identical conditions, totalling 720 measurements per observer. Statistical analysis, comparing both observers and ratios, was carried out using the intraclass correlation coefficient.

Before operation there was greater interobserver variation using either the Insall-Salvati or modified Insall-Salvati ratios than when using the Caton-Deschamps or Blackburne-Peel methods. This was because of difficulty in identifying the insertion of the patellar tendon. Before operation, there was a minimal difference in reliability between these methods. After operation the interobserver difference was greatly reduced using both the Caton-Deschamps and Blackburne-Peel methods, which use the prosthetic joint line, compared with the Insall-Salvati and modified Insall-Salvati, which reference from the insertion of the patellar tendon.

The theoretical advantage of using the Insall-Salvati and modified Insall-Salvati ratios in measuring true patellar height after total knee arthroplasty needs to be balanced against their significant interobserver variability and inferior reliability when compared with other ratios.

We investigated the prognostic indicators for collagen-covered autologous chondrocyte implantation (ACI-C) performed for symptomatic osteochondral defects of the knee.

We analysed prospectively 199 patients for up to four years after surgery using the modified Cincinnati score. Arthroscopic assessment and biopsy of the neocartilage was also performed whenever possible. The favourable factors for ACI-C include younger patients with higher pre-operative modified Cincinnati scores, a less than two-year history of symptoms, a single defect, a defect on the trochlea or lateral femoral condyle and patients with fewer than two previous procedures on the index knee. Revision ACI-C in patients with previous ACI and mosaicplasties which had failed produced significantly inferior clinical results. Gender (p = 0.20) and the size of the defect (p = 0.97) did not significantly influence the outcome.

Autologous chondrocyte implantation (ACI) is used widely as a treatment for symptomatic chondral and osteochondral defects of the knee. Variations of the original periosteum-cover technique include the use of porcine-derived type I/type III collagen as a cover (ACI-C) and matrix-induced autologous chondrocyte implantation (MACI) using a collagen bilayer seeded with chondrocytes. We have performed a prospective, randomised comparison of ACI-C and MACI for the treatment of symptomatic chondral defects of the knee in 91 patients, of whom 44 received ACI-C and 47 MACI grafts.

Both treatments resulted in improvement of the clinical score after one year. The mean modified Cincinnati knee score increased by 17.6 in the ACI-C group and 19.6 in the MACI group (p = 0.32). Arthroscopic assessments performed after one year showed a good to excellent International Cartilage Repair Society score in 79.2% of ACI-C and 66.6% of MACI grafts. Hyaline-like cartilage or hyaline-like cartilage with fibrocartilage was found in the biopsies of 43.9% of the ACI-C and 36.4% of the MACI grafts after one year. The rate of hypertrophy of the graft was 9% (4 of 44) in the ACI-C group and 6% (3 of 47) in the MACI group. The frequency of re-operation was 9% in each group.

We conclude that the clinical, arthroscopic and histological outcomes are comparable for both ACI-C and MACI. While MACI is technically attractive, further long-term studies are required before the technique is widely adopted.

Aims: Anterior knee pain is a common complaint of mixed aetiology, and in many cases no demonstrable cause is identified. For patients with persistant anterior knee pain, tibial tubercle transfer (TTT) can be a surgical option. The aim of this study is to assess the effectiveness of TTT for chronic anterior knee pain resistant to conservative treatment. Method: All patients with arthroscopically proven Chondromalacia patellae (CMP) without clinical evidence of patella instability, who have failed to respond to conservative treatment such as physiotherapy were included in the trial. They underwent TTT with a modified Fulkerson technique and then routine post-operative care with a cricket pad splint for 2–4 weeks. Pre and post-operative scores were obtained using a Kujala patello-femoral score, a visual analogue score for pain and a patient satisfaction score. The Outerbridge grading was used to score the severity of CMP at arthroscopy. Results: There were 50 TTT’s followed up (7 staged bilaterals) with a mean follow up of 32.4 months (5–88 months). There were significant improvement in the pre-operative and post-operative Kujala (p> 0.001) and visual analogue pain scores (p> 0.001). Of the 50 TTT’s 70% had an excellent or good result and 30% a fair or poor result. Moreover 76% claimed that they would have the same operation again for their condition. There was no significant correlation between Outerbridge grading and post-operative outcome. Complications include late anterior knee pain (10 cases), superficial wound infection (1 case), non-union of osteotomy (1 case) and tuberosity fracture (1 case). Conclusion: Anteromedial tibial tubercle transfer is a reliable and effective treatment for peristant anterior knee pain

The aim of this study was to assess the outcome of patients who underwent ElmslieTrillat antero-medial tibial tubercle transfer for treatment of persistent symptomatic anterior knee pain due to chondromalacia patellae. We performed a prospective analysis of 23 patients who underwent Elmslie-Trillat antero-medial tibial tubercle transfers over a five year period for chronic anterior knee pain and an arthroscopic diagnosis of chondromalacia patellae. All patients who presented with anterior knee pain underwent an initial period of physiotherapy and all patients whose symptoms persisted following physiotherapy underwent arthroscopic assessment. Patients who continued to experience debilitating symptoms despite this initial treatment and who also had a diagnosis of chondromalacia patellae from arthroscopic assessment were listed for an Elmslie-Trillat tibial tubercle anteromedialisation. Patients who gave a history of instability or dislocation were excluded. The average age of patients undergoing surgery was 34 years (21–48 years) and the average time between arthroscopic diagnosis and surgery was 14 months. All patients who underwent surgery had pre and post operative KuJala patellofemoral scoring. The average pre-operative score was 54 (30–78) and post operative score 76 (46–100). The average post operative assessment was 25 months (6–62 months). Twenty one patients had improved post operative scores with one having a worse score and one score remaining unchanged following surgery. Nineteen patients felt that their symptoms had improved, three felt that there had been no change and one felt that they were worse after surgery. When asked if the improvement in symptoms had been worthwhile nineteen stated that they would undergo surgery again if in the same situation and four stated that they would not. The treatment of symptomatic chondromalacia patellae remains a challenge. Although a more selective approach to individuals with anterior knee pain is widely advocated in the literature this study demonstrates that good results can still be achieved in patients treated empirically with a tibial tubercle anteromedialisation