Validation of a functional method for the estimation of hip joint centre location.

The present study assesses the accuracy with which the subject specific coordinates of the hip joint centre (HJC) in a pelvic anatomical frame can be estimated using different methods. The functional method was applied by calculating the centre of the best sphere described by the trajectory of markers placed on the thigh during several trials of hip rotations. Different prediction methods, proposed in the literature and in the present investigation, which estimate the HJC of adult subjects using regression equations and anthropometric measurements, were also assessed. The accuracy of each of the above-mentioned methods was investigated by comparing their predictions with measurements obtained on a sample of 11 male adult able-bodied volunteers using roentgen stereophotogrammetric analysis (RSA), assumed to provide the true HJC locations. Prediction methods estimated the HJC location at an average rms distance of 25-30 mm. The functional method performed significantly better and estimated HJCs within a rms distance of 13 mm on average. This result may be confidently generalised if the photogrammetric experiment is carefully conducted and an optimal analytical approach used. The method is therefore suggested for use in motion analysis when the subject's hip range of motion is not limited. In addition, the facts that it is not an invasive technique and that it has relatively small and un-biased errors, make it suitable for regression equations identification with no limit to sample size and population typology.

Cryo/Cuff use after arthroscopic surgery: effect on knee joint temperature.

Any modality that alters joint homeostasis could have a potential negative effect on cartilage. During arthroscopic knee surgery, the temperature in the knee joint decreases significantly. The use of cryotherapy after this surgical procedure could maintain or increase these temperature variations. This prospective, randomized study evaluated the change in intra-articular knee temperature with the use of the Cryo/Cuff (Aircast Inc, Summit, New Jersey) in 30 patients after arthroscopic knee surgery. In 15 patients, a Cryo/Cuff with an automatic pump was applied immediately after surgery (group 1), and in the remaining 15 patients, only a wound dressing was applied (group 2). The mean intra-articular temperature at the beginning of the procedure was 34.8+/-1 degrees C for both groups. At the end of surgery, the temperature was 26.8+/-2.2 degrees C for group 1 and 27.5+/-2.2 degrees C for group 2. One hour after the end of the procedure, the mean temperature was 34+/-1.6 degrees for group 1 and 34.8+/-1.7 degrees C for group 2. These differences were not statistically significant. These results demonstrated that the use of the Cryo/Cuff does not alter temperature recovery in the knee, thereby excluding potential damage to the articular cartilage.

Arthroscopic intra- and extra-articular anterior cruciate ligament reconstruction with gracilis and semitendinosus tendons.

Numerous surgical procedures have been developed and used for anterior cruciate ligament (ACL) reconstruction. Patellar tendon is probably the most common graft used, but gracilis and semitendinous tendons present some interesting advantages: small incision, large graft when doubled, characteristics close to ACL, rapid harvest. We describe a combined intra- and extra-articular arthroscopic ACL reconstruction using hamstring tendons which includes some original steps. The tendons are harvested, leaving the distal insertion intact, and sutured together. After drilling of the tibial tunnel, an over-the-top arrangement is formed, creating a groove in the posterolateral aspect of the femur. The tendons are then fixed with double staples in the groove, and their remaining part is fixed distally to Gerdy's tubercle passing under the fascia, but over the lateral collateral ligament (LCL). This technique ensures sufficient strength in the graft and permits correction of any associated instability, because of the presence of the extra-articular portion of the tendons. Furthermore, the over-the-top arrangement reduces trauma and possible pitfalls related to tunnel construction and permits isometry of the extra-articular portion to be established. Forty patients involved in sports activity were prospectively selected and evaluated at a minimum 2 years' follow-up. IKDC score and Lysholm score were used for clinical evaluation, and the KT-2000 was used for instrumental laxity measurements. Resumption of sport and time to that point were recorded as well as Tegner activity score. We had 92.5% normal and fairly normal knees according to IKDC score and only 7.5% abnormal knees. Mean Lysholm score was 95. Mean Tegner score was 7.2. KT-2000 showed a mean injured/uninjured difference of 2.1 mm. In all, 90% of patients resumed sports at the same level, 67.5% in 3-4 months and 27.5% in 4-6 months. The highly satisfactory results of this series with no major complications confirm the reliability of this technique and the possibility of guaranteeing functional behaviour in the knee.

Total knee arthroplasty without patellar resurfacing in active and overweight patients.

Overweight patients are often considered poor candidates for total knee arthroplasty (TKA). A retrospective study of this was done on 47 osteoarthritic knees treated by TKA without patella resurfacing between March 1991 and June 1993. The Hospital for Special Surgery (HSS) rating system was used for clinical evaluation, and radiographs to study the degree of osteoarthritis and radiolucency. Correlations between overweight, range of motion (ROM) and stage of patellar damage and other measured variables (HSS score, patellar pain and radiolucency) were studied. Overweight was not correlated with HSS score, radiolucency or patellar pain. ROM was significantly correlated with patellar pain and HSS score, with better results in patients with ROM between 90 degrees and 110 degrees. Therefore, we believe that TKA in osteoarthritic knees can lead to successful results, even in active or overweight patients.

Arthroscopic management of recurrent anterior dislocation of the shoulder: analysis of technical modifications on the Caspari procedure.

Arthroscopic treatment was performed on 71 patients with recurrent shoulder dislocations; all of the patients had monoplanar anterior instability attributable to arthroscopically diagnosed Bankart lesion. Of the 71 operations, 29 were performed using the original Caspari technique (follow-up, 59 months), and 42 were performed after modifications made in the original technique (follow-up, 38 months), notably improved preparation of the capsular reinsertion zone and increase in the number of monofilament points and their anchorage directly to the bone, on the spine of the scapula. We compared the results obtained in these two differently treated groups, taking into account several factors in the patient's history and clinical condition. These included the number of dislocation episodes before the operation, as well as clinical findings regarding stability, movement, function and pain (Rowe scale score), contralateral shoulder laxity, level of preoperative versus postoperative athletic activity, and postoperative recurrence rate. In the Caspari-treated group, we obtained 66% satisfactory results compared with the 90% obtained in the second group. The recurrence rate was 27% in the first group compared with 4.8% in the second group. These data were statistically significant. No correlation was found between preoperative number of dislocations and recurrence rate, nor for contralateral shoulder laxity. No significant difference was found regarding resumption of sport activity in the two groups. Our data indicate that, with accuracy in patient selection and effective surgical technique, the recurrence rate can be reduced, and results similar to those of the arthrotomic technique may be obtained.

Arthroscopic reconstruction of the anterior cruciate ligament with Leeds-Keio ligament in non-professional athletes. Results after a minimum 5 years' follow-up.

We report our experience using the Leeds-Keio artificial ligament for anterior cruciate ligament (ACL) reconstruction. The study relates the results of the first 40 patients subjected to arthroscopic reconstruction of the ACL with a Leeds-Keio ligament, with a mean follow-up of 73 months. No associated peripheral procedures were carried out on any patient. The average age of the patients at the time of the operation was 31 years (range 26-35 years). The rehabilitation protocol followed by all patients aimed at resumption of sport 4 months after the operation. Clinical assessment included IKDC and the Lysholm scoring scale. The KT-2000 system was used for instrumented evaluation of joint laxity. All patients underwent a radiographic check-up. Clinically there were 55% excellent or good results when using the IKDC scale, while with the Lysholm score, satisfactory results were obtained in 80%. Complete post-traumatic rupture of the ligament was observed in three patients. No patient suffered an episode of either hydrarthrosis or reactive synovitis, which indicates good tolerance to the ligament. The radiographic evaluation of the operated knees showed a close correlation between the appearance of degenerative phenomena and performance of arthroscopic meniscectomy. The results achieved with the Leeds-Keio artificial ligament 5 years after application, although not completely satisfactory and inferior to those obtained with autologous biological ligaments, should be considered an encouragement to promote new efforts in this interesting research field.

Early versus late reconstruction for anterior cruciate ligament rupture. Results after five years of followup.

We investigated the clinical and laxity testing results at 5 years' followup in patients who had early or late anterior cruciate ligament reconstruction. Twenty-three patients (Group I) were treated within 15 days of injury. Fifty-nine patients (Group II) were treated more than 3 months after injury. Patellar tendon reconstruction and fascia lata graft augmented with a ligament augmentation device were the techniques used in both groups. According to the International Knee Documentation Committee rating scale, 17 patients in Group I and 38 patients in Group II had satisfactory results. The Lysholm score was good in all Group I patients and in 55 Group II patients. Flexion-extension deficits were comparable for both groups. Eighteen patients (78%) in Group I demonstrated satisfactory results according to the KT-2000 arthrometer testing, compared with 44 (75%) in Group II. No associated lesions were present in 12 (52%) cases in Group I, compared with 26 (44%) cases in Group II. Return to sports at the preoperative level was obtained by 21 (91%) patients in Group I, compared with 42 (71%) in Group II. The patients who had reconstruction during the early phase returned to sports activities sooner and had better clinical and laxity testing results.

The preliminary results of press-fit knee arthroplasty without a patellar component.

A total of 22 cases of Kinemax prostheses implanted consecutively from January to June 1990 for the treatment of primary gonarthrosis were evaluated; in these cases remodeling of the patella was performed, and the corresponding component of the prosthesis was not used. The mean age of the patients was 64 years, mean follow-up was obtained after 48 months. According to the HSS form results were: excellent: 9 (40.9%); good: 12 (54.5%); fair: 1 (4.6%). The postoperative femorotibial axis measured a mean of 173.8 degrees. There were no complications in the patella, only in 1 case did we observe mild anterior pain. Knee arthroplasty without substitution of the patella seems to guarantee good results in patients with primary gonarthrosis, as long as patellar reconstruction is performed and correct femoropatellar alignment is guaranteed, as well as recovery of the femorotibial axis with accurate positioning of the prosthetic components.

Results in the treatment of recurrent dislocation of the patella after 30 years' follow-up.

The authors compare the clinical and radiographic outcome in patients with comparable bilateral recurrent patellar dislocation treated surgically on only one side, to clarify the appropriateness of the surgical indication. Sixteen patients were evaluated at an average follow-up of 30 years (20-45); all had been treated by the Roux technique. The results on both the operated and the unoperated knee were evaluated; the Crosby and Insall schedule was used for the clinical evaluation. Anteroposterior, lateral, and Merchant's view X-rays were examined for osteoarthritis and to measure the height of the patella. The congruence angle and the distance between anterior tibial tuberosity and trochlear groove (ATT-TG) were measured by computed tomography. The results in the operated knees were: 3 excellent, 9 good, 1 fair, and 3 worse; results in the nonoperated knees were 6 excellent, 8 good, 1 fair, and 1 worse. In the operated knees arthritis was grossly marked in 8, marked in 3, moderate in 1, and light in 4; in the nonoperated ones it was grossly marked in 8, moderate in 3, and light in 5. The congruence angle was normal in 10, medially displaced in 3, and laterally displaced in 3 cases on the operated side; on the nonoperated side it was normal in 7 cases and lateralized in the remaining 9. The ATT-TG in the operated knees was negative in 9 cases, normal in 1, and positive in 6; on the non-operated side it was positive or normal. In 7 operated cases a low patella was documented. The Roux technique yields positive results in the correction of recurrent dislocation. No clinical or radiographic differences were found between surgically and conservatively treated knees. The clinical results are generally not comparable with the radiographic features or with severity of degenerative modifications presented at long-term follow-up. The absence of a difference is due basically to the complete lack of adaptation of the surgical procedure to the variable pathogenesis of this disorder.