Objective Measurement of Medial Joint Space Widening with Percutaneous “Pie Crust” Release of Medial Collateral Ligament during Knee Arthroscopy

Knee arthroscopy may be called the most commonly and increasingly performed orthopaedic procedure. Posterior medial compartment visualization may be quite challenging. The aim of the present study is to detect objective measurement of medial joint space widening with percutaneous “pie crust” release of medial collateral ligament (MCL) during knee arthroscopy. We used this technique for all knees that require any intervention in the posteromedial compartment and for tight knees in which adequate visualization of the posteromedial compartment cannot be obtained. Eighteen patients (18 knees) were included in this study. Patients were evaluated clinically with the Lysholm and Tegner scores at the final office visit. Joint balance, valgus instability, pain or tenderness on MCL region, and numbness over the medial side of the joint were also noted. Measurements of medial joint space (mm) were obtained at three different times with perioperative C-arm images: normal, controlled valgus force, and after pie crusting. The median follow-up time was 9 (6–12) months. Final follow-up Lysholm (p < 0.05) and Tegner scores (p < 0.05) increased significantly compared with preoperative scores. At the final follow-up, there was no pain or tenderness over MCL and there were no signs of saphenous nerve or vein injury. Medial joint space values in after pie crusting increased significantly (p < 0.05) compared with neutral position measurements and controlled valgus force application (p < 0.05). Controlled release of the MCL in knees provided ∼2.45 times wider visualization place. Furthermore, pie crusting of MCL is a safe and effective technique that provides enough space for visualization and instrumentation in knees. This is a Level IV study.

Traction force for peroperative hip dislocation in hip arthroscopy

Objectives: Traction force widens the joint space during hip arthroscopy. It is unclear how much the traction force varies and if it is related to the joint space widening. Main goal of our study was to measure the amount of force needed to widen the hip joint. Second goal was to study the relation between this force and the amount of joint space widening. Methods: Traction force was measured in 27 patients (of whom 24 female, mean age 41) during arthroscopy. Measurements were performed before the procedure, after vacuum seal release and after capsulotomy. Joint space widening was measured with fluoroscopy and was calibrated. Friedman and Wilcoxon tests were used to measure differences in traction. The Spearman’s rho correlation coefficient was used to identify a correlation in traction force and joint space widening. Regression analyses were used to identify relations between age, body mass index (BMI), hip degeneration and traction force. Results: The median traction force before arthroscopy was 714 N, lowered to 520 N after vacuum seal release and to 473 N after capsulotomy ( p < 0.001). Median joint space widening was 8.8 mm. Spearmans’ rho correlation between traction force and joint space widening was ‒0.13. Discussion: Median traction force of 714 N resulted in 8.8 mm of joint space widening. This traction force was significantly lowered by 200 N after release of the vacuum seal of the hip and 250 N after additional capsulotomy without loss of joint space narrowing. No significant relation was identified for age, BMI or progression of the Kellgren-Lawrence classification for hip degeneration and traction force. Netherlands Trial Registry number 8610

Joint space widening may be a paradoxical pathologic feature of early ankle arthritis

Category: Ankle, Ankle Arthritis Introduction/Purpose: Joint space narrowing and bony spur are typical pathologic feature of early ankle osteoarthritis. The meaning of joint space widening has never been discussed in previous literature. However, we found some osteoarthritic ankles which showed joint widening with diffuse spur change.(Fig.1) We hypothesized that joint space widening may be caused by malpositioning of the talus which may lead to degenerative arthritis. The purpose of this study were to investigate the radiological abnormalities in ankles with joint space widening. Methods: In order to define joint space widening and anterior subluxation of the talus, we included 72 ankles (66 people) with no abnormalities on plain radiographs into control group. We measured joint space and lateral talar station(LTS) on plain weight- bearing radiographs.(Fig.2) The 95% prediction interval of joint space (2.4 mm to 4.2 mm) and the LTS (-0.9 mm to 3.8 mm) in the control group were regarded as a normal range. The joint space widening was defined when the joint space was wider than 4.2 mm, and the anterior subluxation of talus was defined when the LTS was larger than 3.8 mm. Thirty-two ankles (29 people) with the joint space widening which underwent operation in our clinic between 2009 and 2014 were included in patient group. Ankle instability was determined on stress radiographs (Fig.2). In the patient group, we investigated the anterior subluxation of talus and the ankle instability, and the sites of spur in conventional CT. Results: The average age was 26 years (range:18 - 35) in the control group and 33 years (range:16 - 71) in the patient group. The mean joint space of the patient group was 4.7 mm (range: 4.3 mm to 6.0 mm). In the patient group, the LTS showed a mean of 6.4 mm (range 3.9 mm -10.7 mm). Because all the LTS in the patient group was over the 3.8 mm, the anterior subluxation of talus was showed in all ankles of the patient group. In the patient group, 31 ankles (97%) showed instability on anterior stress radiograph and 24 ankles (75%) showed instability on varus stress radiograph. All ankles in the patient group showed spurs on 4 sides of ankle, anterior, posterior, medial and lateral side. Conclusion: This study showed that paradoxical joint space widening may be a pathologic feature of early ankle arthritis which had diffuse spur change, anterior displacement of the talus and ankle instability.