Pascal Kouyoumdjian

A Preliminary In Vivo Assessment of Anterior Cruciate Ligament–Deficient Knee Kinematics With the KneeM Device: A New Method to Assess Rotatory Laxity Using Open MRI

Background: Methods of objectively measuring rotational knee laxity are either experimental or difficult to use in daily practice. A new method has been developed to quantitatively assess rotatory laxity using an open MRI system and new tool, the KneeM device. Purpose/Hypothesis: To perform a preliminary evaluation of a novel knee rotation measurement device to assess knee kinematics during flexion in an MRI field, in both anterior cruciate ligament (ACL)–deficient and healthy contralateral knees. The hypothesis was that the KneeM device would allow in vivo reproduction and analysis of knee kinematics during flexion in healthy and ACL-deficient knees. Study Design: Controlled laboratory study. Methods: Ten subjects (7 men and 3 women; mean age ± standard deviation, 32.3 ± 9.4 years) with ACL-deficient knees and contralateral uninjured knees participated in the study. An open MRI was performed with the KneeM device at a mean 4.9 months (range, 3.0-7 months) after ACL injury. The device exerted on the knee an anterior drawer force of 100 N, with an internal rotation of 20°, through the range of flexion (0°, 20°, 40°, and 60°). Both ACL-deficient and healthy contralateral knees were analyzed using the Iwaki method. Results: There was no statistical difference of anterior translation in the medial compartment between intact and ACL-deficient knees at all degrees of flexion. However, significant differences in the anterior translation of the lateral compartment were observed between ACL-deficient and intact contralateral knees at 0° and 20° of flexion (P = .005 and P = .002, respectively). Between 20° and 40°, the lateral plateau of ACL-deficient knees translated 7.7 mm posteriorly, whereas the medial compartment remained stable, reflecting a sudden external rotation of the lateral plateau under the femoral condyle. Conclusion: This preliminary study suggests that measurement of tibiofemoral movements in both compartments during flexion using the KneeM device was useful for quantifying rotatory laxity in ACL-deficient knees. Moreover, this device seemed to allow a “mechanized pivot shift” and allowed reproduction of the “pivot” phase in the MRI field between 20° and 40° of flexion. Clinical Relevance: This device could be used for diagnostic purposes or to investigate the outcomes of ACL reconstructions.

Surgeon's and patient's radiation exposure during percutaneous thoraco-lumbar pedicle screw fixation: A prospective multicenter study of 100 cases

HYPOTHESIS Percutaneous pedicle screw fixations (PPSF) are increasingly used in spine surgery, minimizing morbidity through less muscle breakdown but at the cost of intraoperative fluoroscopic guidance that generates high radiation exposure. Few studies have been conducted to measure them accurately. MATERIAL AND METHODS The objective of our study is to quantify, during a PPSF carried out in different experimented centers respecting current radiation protection recommendations, this irradiation at the level of the surgeon and the patient. We have prospectively included 100 FPVP procedures for which we have collected radiation doses from the main operator. For each procedure, the doses of whole-body radiation, lens and extremities were measured. RESULTS Our results show a mean whole body, extremity and lens exposure dose per procedure reaching 1.7±2.8μSv, 204.7±260.9μSv and 30.5±25.9μSv, respectively. According to these values, the exposure of the surgeons extremities and lens will exceed the annual limit allowed by the International Commission on Radiological Protection (ICRP) after 2440 and 4840 procedures respectively. CONCLUSION Recent European guidelines will reduce the maximum annual exposure dose from 150 to 20mSv. The number of surgical procedures to not reach the eye threshold, according to our results, should not exceed 645 procedures per year. Pending the democratization of neuronavigation systems, the use of conventional fluoroscopy exposes the eyes in the first place. Therefore they must be protected by leaded glasses. LEVEL OF PROOF IV, case series.

Does Endoscopic Piriformis Tenotomy Provide Safe and Complete Tendon Release? A Cadaver Study

BACKGROUND Endoscopic piriformis release (EPR) is among the available treatments for piriformis syndrome. This procedure typically involves dividing the muscle near the sciatic nerve in the sub-gluteal space, which contains numerous blood vessels and nerves. The objectives of this prospective cadaver study were: 1) to assess the reproducibility and quality of endoscopic piriformis tenotomy near the greater trochanter; 2) to detect iatrogenic injuries to the lateral hip rotators, nerves, and vessels; 3) and to define the surgical safety margins relative to the sciatic nerve and inferior gluteal bundle. HYPOTHESIS EPR at the greater trochanter ensures full release of the muscle with a limited risk of neuro-vascular injury. MATERIAL AND METHODS EPR was performed via two portals on 10 cadaver hips preserved in zinc chloride and placed in the prone position. A third, ancillary portal was required in 7 cases. The area was then dissected with the Kocher-Langenbeck approach to allow an assessment of the tenotomy, detect iatrogenic injuries, and measure the distances separating the tenotomy site from the sciatic nerve and inferior gluteal artery. RESULTS Complete tenotomy was achieved in 9 (90%) cases. The tendon adhered to the capsule in 2 (20%) cases and showed acquired avulsion in 1 case. No injuries to the sciatic nerve or inferior gluteal artery occurred. Mean distances from the tenotomy site were 5.21±0.59cm (range, 4.5-6.6cm) for the sciatic nerve and 7.1±0.89cm (range, 5.4-8.5cm) for the inferior gluteal artery. DISCUSSION EPR by a tenotomy at the greater trochanter without sciatic nerve release provides full release of the muscle with satisfactory safety margins and a short learning curve. LEVEL OF EVIDENCE III, prospective cadaver case-control study.

Arthroscopic Dorsal Capsuloplasty in Scapholunate Tears EWAS 3: Preliminary Results after a Minimum Follow-up of 1 Year

Purpose We retrospectively evaluated the results of all arthroscopic dorsal scapholunate (SL) capsuloplasty without pinning in patients presenting predynamic instability and dorsal capsuloscapholunate septum lesions on arthro‐computed tomography scan after failed medical treatment. Materials and Methods Fifteen patients, mean age 34.3 years, underwent all arthroscopically assisted dorsal capsuloplasty. Patients were assessed preoperatively and postoperatively by a clinical (pain, Watsons test, range of motion, and strength), functional (quick disabilities of the arm, shoulder, and hand), patient‐rated wrist evaluation, and Mayo wrist score scores), and radiological (SL gap and dorsal intercalated segmental instability [DISI]) examination. SL tears were evaluated during surgery by European Wrist Arthroscopy Society (EWAS) classification. Results The mean follow‐up period was 20.2 months (range, 12‐41). Preoperatively, positive Watsons test was noted in all cases. DISI deformity was noted in three cases without any SL gap. The SL instability was graded EWAS IIIB (n = 8) or EWAS IIIC (n = 7). Postoperatively, positive Watsons test was noted in only one case. Activity pain decreased from 7.8 preoperatively to 2.4 postoperatively. Range of motion in flexion‐extension increased from 92.9 degrees preoperatively to 126.2 degrees postoperatively. Grip strength increased from 24.2 preoperatively to 38.2 postoperatively. At final follow‐up, range of motion in flexion‐extension and grip strength were estimated at 87 and 91% compared with contralateral side, respectively. All functional scores were significantly improved at the last follow‐up. No radiographic SL gapping in grip views or DISI deformity was noted. Discussion Cadaveric studies demonstrated that the dorsal portion of SL ligament is critical for the stability of the SL complex. The entire arthroscopic SL capsuloplasty technique provides reliable results for pain relief, avoiding postoperative stiffness associated with open procedures. It is an alternative technique for patients with predynamic SL instability after failure of medical management and shall not prelude the resort to any further open procedure. Level of Evidence This is a level IV, case series.

Bilateral simultaneous endoscopic carpal tunnel release: Mean time to resume activities of daily living and return to work

The purpose of this study was to determine the time needed to return to personal and professional activities after bilateral simultaneous endoscopic carpal tunnel release. During a retrospective, single-center study, we included a cohort of 30 patients (60 wrists). Patients were evaluated clinically (pain, paresthesia) and functionally (QuickDASH score) pre- and postoperatively. At the last follow-up, patients completed a questionnaire regarding the time needed to resume personal activities using the ADL scale (feeding, personal hygiene and dressing) and return to work. We also evaluated procedure satisfaction and willingness to undergo the surgery again. The average patient age was 60.5 years (range 39-86). At the last follow-up, average time to resume personal activities was 2.2 days (0-14) for feeding, 4.4 days (0-15) for personal hygiene and 3.9 days (0-14) for dressing. Average time to return to recreational activities was 11.7 days (1-60). Average time to return to work was 36.6 days (15-60). Overall, 97% of patients were satisfied or very satisfied with the outcome. All patients would have the bilateral simultaneous surgery again. Bilateral simultaneous endoscopic carpal tunnel release is rarely performed. For mild conditions, contralateral symptom improvement is common after unilateral surgery. Bilateral simultaneous endoscopic carpal tunnel release appears to be disabling right after surgery, but clinical and functional scores are similar after the third postoperative day. These data can be used for patient education and decision making when considering surgery bilateral carpal tunnel syndrome. Bilateral simultaneous endoscopic carpal tunnel release is a feasible and safe procedure. LEVEL OF EVIDENCE Level IV, case series.

Effects of chair type on lumbar curvature in patients with low back pain and healthy controls

parameters. Results.– On 16 patients, only 10 questionnaires were usable (questionnaires not filled, evaluation before, after not possible). At the end of 3 weeks, pain is very clearly improved with P 0.013, the score of kinesiophobia also (31.8 vs 41.2) with P in 0.009. The scores of acceptance are improved 27.44 against 21.88 at the exit but not significant with P in 0.14. The scores of change of behavior PSCOQ are all improved for all the patients for the hillside preservation (will to improve its strategies to face) P 0.0057 and no change for the intention. There was also a significant improvement of the anxiety (P in 0.03), not significant for the depression (P in 0.1). The physical parameters (schober, outstrip fingers ground, poplités angles, outstrip heel spank, shirado, sorensen) were improved. Conclusion.– For all the patients, is turned out an increase of the implication of the patient in its care, at the end of the program. It also seems that this type of program brings an improvement of the acceptance of the pain chronic without it is significant on our small population as well as of the capacity to manage better their disease. Studies on a bigger population and a remote follow-up would be desirable.