Purpose of the study: Posterior shoulder instability is a rare condition. Several surgical treatments have been proposed.

Material and methods: This was a retrospective series of 21 posterior bone block procedures performed between 1984 and 2001 and analyzed with mean follow-up of six years. Fifteen patients (n=16) had experienced one or more episodes of posterior dislocation. Thirteen patients were athletes and five had traumatic subluxation with chronic posterior instability. Voluntary recurrent dislocations were not observed in these patients. Male gender predominated (n=19 men, 1 woman). Mean age at surgery was 24.8 years (range 17–40). The dominant side was involved in 12 patients (57%). The Constant and Duplay scores were noted as were the pre- and postoperative x-ray findings. There were ten glenoid fractures, two glenoid impactions, ten anterior humeral notches. Mean retroversion, measured on the scans (n=17) was 9.6° (range 0–21°).

Results: All patients (n=20) were satisfied or very satisfied. At last follow-up, the mean Constant score was 93.3 (range 80–103) and the mean Duplay score (n=21) 85.6 (40–100); 68.2% of patients (n=15) resumed sports activities at the same level. Failure was noted in three patients, one with recurrent posterior dislocation and two with major apprehension. For two patients, glenohumeral osteoarthritis developed postoperatively.

Discussion: Most of the series in the literature have reported results for patients with recurrent posterior subluxations and not for traumatic posterior dislocation, the much more uncommon entity presented here. The rate of bony lesions was high in our series compared with former series in the literature. These results can be explained by two facts. The first that this was a group of recurrent posterior dislocations and second that the analysis of the osteoarticular lesions was made on plain x-rays and/or CT scans. For the two cases of glenohumeral osteoarthritis which developed postoperatively, the position of the bone block does not appear to be involved.

Conclusion: The posterior bone block remains the treatment of choice for recurrent posterior dislocation. The risk of developing osteoarthritis appears to be low but a longer follow-up would be necessary for confirmation.

Purpose of the study: Cysts are rarely identified in the anterior cruciate ligament; the pathogenic mechanisms involved are poorly understood. We investigated the anatomic and clinical presentation.

Material and methods: This retrospective analysis included 24 patients, seven women and seventeen men managed in a single center from 1998 to 2004. Mean patient age was 45 years (range 25–74 years). All patients complained of pain. A preoperative MRI was available for all patients. Mean follow-up was 25 months (range 6–48 months). Arthroscopic procedures were used for 17 patients and the IKDC subjective score was determined preoperatively in all. Radioguided (US or CT) puncture was performed for seven patients associated with corticosteroid injections.

Results: On the MRI, there were 16 infiltrating cysts and eight cystic formations. Surgical treatment (n=17) was performed for 13 infiltrative cysts and for four cystic formations. There were two cases of recurrence. Outcome was poor after puncture (two puncture failures, three recurrences and one vascular complication).

Discussion: Two forms of cysts of the ACL can be demonstrated by MRI. The clinical presentation may not be different but the therapeutic management should be. The cystic formation is an indication for puncture, with arthroscopic treatment in the event of failure. For infiltrating cysts, complete resection of the cyst during an arthroscopic procedure is indicated, sometimes associated with resection of the ACL. Puncture yields poor results.

Purpose of the study: The purpose of this retrospective study was to analyze clinical datao n pigmented villon-odular synovitis (PVSN) of the knee as well as outcome after treatment in order to define the diagnostic stages, the surgical treatment, and follow-up modalities for this rare benign proliferative disease of the synovial which predominantly affects the knee joint.

Material and methods: Between 1996 and 2004, 28 patients were managed in our department, 13 men and 15 women, diffuse PVNS in 20 and localized PVNS in 8. IN the localized forms, symptoms were similar to those observed in knees with intra-articular foreign bodies or a meniscal lesion (75%) was present for 14 months on average at the first consultation. Mean age at onset of therapeutic management was 40 years (range 20–62). Localized arthroscopic or open resection was performed. For the diffuse forms, symptoms had been present for 15 months on average at the first consultation. Patients sought medical care because of spontaneous hemarthrosis or diffuse knee pain with no specific signs. Mean age at onset of therapeutic management was 38 years (range 15–59). Bony lesions were observed in 20%. Synoviorthesis or surgical synovectomy were performed. Mean follow-up was 97 months (range 12–309). Outcome was analyzed separately for the localized and diffuse forms.

Results: For the localized PVNS, there were no complications after surgical treatment but the relapse rate reached 12.5%. For diffuse PVNS, the cumulative rate of relapse was 50%, recurrence being noted on average 37 months after treatment. A stiff joint developed in 14% after open synovectomy. Surgical treatment was necessary in four cases (total arthroplasty in three) seen late after development of bony lesions; the clinical outcome was good with good gain in flexion.

Discussion: MRI is essential for the topographic diagnosis and to guide surgery. For diffuse PVNS seen at an advanced stage or after several recurrences, adjuvant synoviorthesis can be useful 4 to 8 months after surgery.

Conclusion: Appropriate treatment of PVNS of the knee depends on the presentation but usually involves a surgical procedure. The risk of recurrence for diffuse PVNS warrants annual MRI for four years.

Purpose: One of the difficult problems during the implantation of a total knee prosthesis is the presence of preoperative stiffness or permanent flexion.The later is a sign of advanced stage degradation due to osteoarthritis or rheumatoid arthritis. We wanted to describe the technical specificities of a total knee arthroplasty (TKA) implanted in patients with permanent flexion and to analyse long-term outcome.

Material and methods: We studied a series of 826 posterior stabilised TKA (HLS) implanted since 1988 (followed prospectively since 1995). We defined three groups of patients according to the degree of preoperative flexion: group I (0°–10°), group II (11°–20°), and group III (> 20°). We evaluated the operative technique itself, then analysed long-term clinical and radiological outcome using the IKS scores.

Results: There was no significant difference in the objective or subjective clinical or radiological outcomes in the first two groups (I and II). Outcome appeared to be less satisfactory in patients with permanent flexion greater than 20°, but the statistical analysis was not feasible.

Discussion: This study enabled us to describe the specific preoperative planning and the operative steps necessary for patients with permanent flexion preoperatively. The results of our series do no enable distinction between the long-term results in patients with < 20° flexion. Beyond this level, techniques for bony or ligamentary release influence the results which are less satisfactory. Posterior stabilisation enables release of the posterior cruciate ligament in order to improve joint recovery.

Conclusion: Preoperative planning for TKA must of course take into account bony deformation, but also preoperative joint motion. In the event of permanent flexion, the operative technique must be adapted. This allows correct position of the implant and improved joint motion.

Purpose: The purpose of this work was to report mid-term results of a series of 162 total knee prostheses with an all-polyethylene plateau.

Material and methods: Between 1989 and 1995, 162 posterior stabilised cemented HLS2 total knee prostheses with an all-polyethylene plateau were implanted during first intention arthroplasties performed by the same surgeon. 142 prostheses were reviewed at more than one year, three patients died, and 17 were lost to follow-up (10%). Clinical results were assessed with the IKS criteria. Complete x-ray data included pangonograms. Mean follow-up was 4.5 years.

Results: Ninety-six percent of the patients were satisfied or very satisfied and 95% had no pain or mild pain. Mean flexion was 114°. The mean postoperative knee score was 81/100 and mean function score was 64/100. Radiographic findings showed the good position of the implants with mean AFT at 178.6°, mean AFm at 89.1° and mean ATm at 89°. There were eight failures (4.9%) requiring replacement of a component, two for frontal laxity, three for patellar fracture, one for infection, one for aseptic loosening, and one for an oversized tibial plateau. Two revision procedures were performed without implant replacement, one for pain (biopsy) and one for arthrolysis.

Discussion: These 162 prostheses with an all-polyethyl-ene plateau were retained among a consecutive series of 893 HLS prostheses. We compared the present results with those of the metal-backed prostheses implanted in this series and with data in the literature. We found a significant correlation between the presence of tibial lucent lines and postoperative alignment defects, explained by the type of tibial component, in these 162 all-polyethyl-ene plateau prostheses. These lucent lines did not progress with time and had no clinical consequence.

Conclusion: Clinial and radiological results with total knee prostheses with an all-polyethylene plateau, i.e. without metal backing, were very good in this series. We analysed our experience in comparison with the literature, focusing on the advantages and disadvantages of these two types of components.

Purpose: The purpose of this work was to analyse functional results in patients with objective patellar instability who underwent surgery between 1988 and 1999.

Material and methods: One hundred eighty knees, 140 patients, were included in this series. Minimum follow-up was two years, and the mean follow-up was five years (range 24 – 152 months). The IKDC 99 subjective knee chart was used for postoperative assessment. This chart has ten items for sports activities and functional status of the knee for everyday activities. Eighty-three percent of the patients (118 patients) responded to the questionnaire.

Results: Clinical assessment was available for 98 patients (63%) and phone interview data for 29 (20%). Subjectively, 111 (94.87%) patients were very satisfied, five (4.27%) were satisfied, and one was dissatisfied. We assessed results by pain level (37.6% mild or weather-related pain), residual oedema, sensation of blockage (15.8%), instability, daily activities (68% with difficulty in the kneeling position), sports activity and level.

Discussion: Certain authors (Insall) question the pertinence of operating objective patellar instability because of the risk of secondary femoropatellar degeneration. For us, surgical treatment is indicated when there has been at least one dislocation associated with morphological anomalies. We have not observed any cases of femoroatellar degeneration among our patients who were operated on more than ten years ago. The patients’ own subjective assessment shows that surgical treatment with medialisation and/or lowering of the tibial tuberosity has been effective with a very excellent rate of satisfaction. The quality of the results is directly related to correct treatment of the lesions (for patients without recurrent dislocation) and systematic analysis of the different factors contributing to patellar instability (trochlear dyplasia, patellar height, quadriceps dyplasia, length of the patellar tendon). Our rate of revision appears to be low but was directly related to the young age of this population and is close to or above the revision rates observed in series with follow-ups greater than two years.

Conclusion: Surgery for objective patellar instability gives good mid- and long-term results. The subjective IKDC score allows precise self-evaluation. We have not been able to find any correlation between subjective results and objective results.