Page 38 - ISAKOS 2019 Newsletter Volume 1

CURRENT CONCEPTS
Microinstability of the Hip: Diagnosis and Treatment
When the patient feels too much pain to do the exercises, an intra-articular cortisone injection may reduce joint irritation and permit proper rehabilitation. We recently reported on the success of nonoperative treatment for hip instability, with over half of the patients avoiding surgery.
If PT fails, surgery is indicated. Hip arthroscopy can be performed according to the surgeon’s preference (lateral vs. supine, outside-in vs. inside-out); however, it is essential that the surgeon is careful with the capsule. Excessive capsulectomies may render closure impossible at the end of surgery. Intraoperative signs of instability include the ease of distraction of the femoral head and / or the lack of reduction of the femoral head when releasing traction. Additionally, the location of labral or chondral lesions should clue the surgeon into the possibility that the patient has instability. Labral tears caused by hip microinstability tend to be more anterior than tears caused by FAI, with a typical location between the 4 and 2-o’clock positions. Ligamentum teres tears may also be a sign of instability. In cases of instability associated with FAI, cam and pincer impingement are corrected by resecting the excess bone in the femur and acetabulum, thereby improving the clearance for hip movement. Labral tears are repaired with anchors. In a patient with an unstable hip, preserving the labrum is paramount; therefore in cases of advanced labral degeneration, a labral reconstruction may be considered2.
At the end of the procedure, a capsular plication is performed in order to tighten the hip capsule and stabilize the joint. Three different techniques have been described in the literature. The capsular shift technique is used when the surgeon performs a capsulotomy from the 12 to 3-o’clock position (in relation to the acetabulum). The capsule is closed with oblique sutures obtaining a bigger bite in the distal capsular flap so that the capsule is imbricated and an inferior capsular shift is produced3. The RICH (rotator interval closure of the hip) technique is performed by completing the central compartment part of the arthroscopy without a capsulotomy4.
When the peripheral compartment is addressed, a small capsulectomy (6 – 8 mm in width and 15 mm in length) is performed in the “bare area” of the hip capsule, between the iliofemoral and the ischiofemoral ligaments, in order to obtain a small capsular window. After the femoral osteoplasty is finished, the capsulotomy is closed, tensioning the capsule. The advantage of this technique is that it avoids iatrogenic injury to the iliofemoral ligament. The third option is the shoelace capsular closure technique5. A capsulotomy is performed in a fashion similar to the capsular shift technique; however, instead of closing the capsule with separate interrupted sutures, a continuous suture is performed, crisscrossing both limbs of the capsule with a strong suture.
The authors believe that this construct is more secure and stable than interrupted sutures. Postoperatively, independent of the technique, a hip brace is used to avoid hip extension, and anti-rotational boots are used to avoid external rotation when the patient is lying down. These restrictions are usually continued for 2 to 3 weeks.
The published results of capsular plication are promising. In a cohort of 22 patients with borderline dysplasia that was treated with the capsular shift technique, 77% of patients had good to excellent outcomes after a mean duration of follow-up of 27.5 months3. In a study of 32 patients who were managed with the RICH technique, the modified Harris hip score increased from 67 to 97 and the iHOT score increased from 41 to 85 after a minimum duration of follow-up of 12 months4. The authors of both studies acknowledged that longer follow-up studies are needed to determine if these favorable results are maintained.
Conclusion
Sports medicine physicians should understand the concept of hip instability and keep this diagnosis in mind when treating young patients who have hip pain, especially females. Rehabilitation is considered the first line of treatment. If conservative treatment fails, a hip arthroscopic plication yields favorable clinical results.
References
1.Hoppe DJ, Truntzer JN, Shapiro LM, Abrams GD, Safran MR. Diagnostic accuracy of 3 physical examination tests in the assessment of hip microinstability. Orthop J Sports Med. 2017 Nov;5(11):2325967117740121. 2. Sharfman ZT, Amar E, Sampson T, Rath E. Arthroscopic labrum reconstruction in the hip using the indirect head of rectus femoris as a local graft: surgical technique. Arthrosc Tech. 2016 Apr;5(2):e361–4. 3. Chandrasekaran S, Vemula SP, Martin TJ, Suarez-Ahedo C, Lodhia P, Domb BG. Arthroscopic technique of capsular plication for the treatment of hip instability. Arthrosc Tech. 2015 Apr;4(2):e163–7. 4. Kalisvaart MM, Safran MR. Hip instability treated with arthroscopic capsular plication. Knee Surg Sports Traumatol Arthrosc. 2017 Jan;25(1):24–30. 5. Uchida S, Pascual-Garrido C, Ohnishi Y, Utsunomiya H, Yukizawa Y, Chahla J, et al. Arthroscopic shoelace capsular closure technique in the hip using Ultratape. Arthrosc Tech. 2017 Feb;6(1):e157–61.
36 ISAKOS NEWSLETTER 2019: VOLUME I