Orthopedic Teaching Cases 2023, Jan, 25 | 12:00 am

Conservative Hip Surgery Case Title: Open Surgical Dislocation of the Hip

Demographics

  1.  

    Age: 25 Sex: Female BMI: 22

     

  2. Relevant Past Medical History

     

    Principal pathologies: Crohn’s disease, obsessive-compulsive disorder

    Previous surgical procedures: None

    Medication: Celexa, Klaron, Remicade, Spironolactone

    Other: N/A

    History of presenting complaint: A 25-year-old female presented with an 8-month history of left hip pain located in the posterior trochanteric area. The pain started after running which then progressed to difficulty with sitting and walking. She denied any mechanical symptoms and a history of trauma. She did not get any relief with physical therapy or a steroid injection into the piriformis. She, did, however obtain 50% pain relief with an intra-articular hip injection.

     

  3. Clinical Examination

     

    Symptoms: Left hip posterior trochanteric pain

    Range of motion: Extension-flexion: 0–110; internal-external rotation at 90 degrees of flexion: 45–45; abduction-adduction: 60–30. Decreased external rotation in extension

    Specific tests: Negative flexion-adduction-internal rotation test (anterior impingement), positive extension-abduction-external rotation test (posterior impingement)

    Main disability: Posterior hip pain and positive posterior impingement

    Scoring if available: N/A

    Neurovascular evaluation: Normal motor and sensory exams (sciatic and femoral nerve distributions). Normal dorsalis pedis and posterior tibial arterial pulses

     

  4. Preoperative Radiological Assessment/Imaging (Figs. 1.31, 1.32, and 1.33)

     

     

     

    Fig. 1.31 Anteroposterior pelvic X-ray demonstrates a prominent left hip posterior acetabular wall. Note the posterior overcoverage (arrows) but normal anterior coverage as depicted by the anterior and posterior wall contours. Also, note the labral ossification posterosuperiorly

     

     

     

     

    Fig. 1.32 Frog leg lateral radiograph demonstrates around the the femoral head with no CAM lesion present

     

     

     

     

     

    Fig. 1.33 Cross-table lateral X-ray that further shows the prominent posterior wall of the left acetabulum

     

  5. Preoperative Planning

     

    Diagnosis: Left hip posterior femoroacetabular impingement (Figs. 1.31, 1.32, and 1.33).

    Possible treatment options: Open surgical hip dislocation with posterior wall trimming and offset procedure, arthroscopic posterior wall trimming.

    Chosen treatment method: Left hip surgical hip dislocation with offset procedure, posterior wall rim trimming, and labral reconstruction with fascia lata.

    Selection of implants if applicable and rational: 2 mm suture anchors for the labral reconstruction with fascia lata, two 3.5 mm cortical screws for the trochanteric fixation.

    Expected difficulties: (1) Treatment of an ossified posterior labrum, (2) intraoperative finding of a CAM lesion.

    Strategies to overcome difficulties: (1) Anticipate the possibility that after rim trimming has been achieved, the labral deficiency will either be accepted, or reconstruction could be performed. In this case, reported grafts include ipsilateral hamstring, allograft labrum, ipsilateral fascia lata autograft, or round ligament. The graft will need to be stabilized with suture anchors to reconstruct the posterior labrum; (2) prepare to inspect the femoral head-neck junction to make sure no CAM lesion is present; and (3) impingement-free range of motion (ROM) should be achieved.

     

  6. Surgical Note

     

    Patient’s position: Right lateral decubitus.

    Type of anesthesia: General anesthesia.

    Surgical approach: Superficial dissection, skin incision similar to the Kocher-Langenbeck approach and associated split of the fascia lata; deep dissection, surgical hip dislocation with greater trochanteric flip osteotomy and Z-shaped capsulotomy.

    Main steps:

     

    1. Skin incision similar to a Kocher-Langenbeck approach to the hip.

    2. Fascial split.

    3. Internal rotation of the leg and identification of the posterior edge of the gluteus medius and the proximal portion of the vastus lateralis.

    4. Greater trochanteric osteotomy is made along the posterior edge from the posterior border of the gluteus medius to the deep posterior portion of the vastus lateralis. The osteotomy is made through the trochanter and not under the trochanteric overhang to avoid injury to the femoral head blood supply.

    5. The fragment is then retracted anteriorly with the attached gluteus medius and vastus lateralis.

    6. Dissection of the interval between the gluteus minimus and piriformis tendons.

    7. Z-shaped capsulotomy with careful dissection not to injure the labrum.

    8. Dislocation with hip flexion and external rotation as well as adduction to deliver the femoral head superficially.

    9. Inspection of the acetabulum. The patient had significant posterior overcoverage, a deep socket, and ossified labrum from the 5 to 11 o’clock position.

    10. Posterior wall trimming using osteotomes and then a burr for final finishing touches (Figs. 1.34 and 1.35).

    11. Fascia lata autograft harvest.

    12. Attachment of the graft to the posterosuperior acetabulum with suture anchors.

    13. Assessment of the femoral head and neck. This patient did not have a CAM lesion, and the cartilage was intact.

    14. Testing of hip ROM.

    15. Closure with fixation of the greater trochanteric osteotomy with two 3.5 mm cortical screws.

       

      Reconstruction techniques: Posterior wall trimming, labrum reconstruction with ipsilateral fascia lata autograft and suture anchors, and greater trochanter fixation with two 3.5 mm cortical screws (Figs. 1.36 and 1.37).

       

  7. Intraoperative Imaging

     

     

     

     

    Fig. 1.34 Intraoperative photograph demonstrates the extent of the patient’s hip external rotation prior to the acetabular rim trimming. The patient is currently in the lateral decubitus position

     

     

     

     

    Fig. 1.35 Intraoperative image shows the increased amount of hip external rotation following rim trimming of the posterior wall of the acetabulum. Note the difference in hip rotation compared to the first image

     

  8. Intraoperative Challenges

     

    Challenges and solutions: Challenge: maintaining femoral head blood supply during surgical hip dislocation; solution: avoid injury to the deep

    branch of the medial femoral circumflex and the anastomosis in between this vessel and the inferior gluteal that runs distally to the piriformis. The use of a Z-shaped capsulotomy with careful dissection posteriorly at the acetabular rim to avoid injuring the labrum. Challenge: inspection of the posterior acetabulum and labrum; solution: elevation of the knee and the use of axial pressure to deliver the head posteriorly to access the posterior rim. Trochanteric reduction and stable fixation. Rehabilitation: toe-touch weight-bearing for four weeks and then weight bearing as tolerated. Challenge: the presence of an ossified labrum with a large area of deficient labrum; solution: the use of fascia lata autograft and suture anchors to reconstruct the deficient labrum.

    Unanticipated problems and solution: Problem: inability to fully visualize the posterior acetabulum; solution: requires release of the anterior capsule, mobilization of the femur, and muscle relaxation helps. Problem: over- or undertrimming the acetabular rim; solution: progressive trimming of the rim with verification of improvements in ROM in extension and external rotation. Problem: fixation of the fascia lata autograft; solution, the graft is tubularized and fixed to the posterior and superior aspect of the acetabulum. The graft was performed as this was a young patient. Problem: trochanteric fixation if a soft bone is encountered; solution: the use of washers is recommended in situations with weak or soft bone.

    Thorough description of decision making, including the reason for the final decision: Intra-articular hip pathology such as posterior femoroacetabular impingement can be very debilitating to patients. Hip arthroscopy has evolved significantly over the years, whereby several hip abnormalities can now be addressed arthroscopically. However, it requires a large learning curve and is unable to address all hip pathology. Among the deformities that are hard to address arthroscopically are those that involve the posterior aspect of the acetabulum. Surgical hip dislocation is an excellent approach to treat intra-articular hip disease both as a first-line surgical approach and when hip arthroscopy is insufficient. Surgical dislocation of the hip was chosen in this case because it was felt that hip arthroscopy would not

     

    be able to address precisely the large area of posterior acetabular overcoverage and potential labrum issues. A precise correction and check for persistent impingement should be carried out in cases with this degree of overcoverage (see intraoperative photographs).

     

  9. Postoperative Radiographs

    (Figs. 1.36 and 1.37)

     

     

     

     

    Fig. 1.36 Anteroposterior pelvic X-ray that shows the trimmed left posterior superior acetabular wall and superior and suture anchors for the labral reconstruction. Please note the distal extent of the rim trimming (arrows). The rim was trimmed down to the attachment of the posterior inferior attachment of the transverse ligament

     

     

     

     

    Fig. 1.37 Cross-table lateral radiograph further delineates the posterior acetabular wall trimming, suture anchor fixation for the labrum, and two screws for the trochanteric fixation

  10. Postoperative Management

     

    Chemoprophylaxis and anticoagulant treatment period: Thromboprophylaxis was provided with 5000 units of Fragmin daily for ten days followed by aspirin 325 mg twice a day for an additional four weeks as well as compression stockings. Spontaneous compression devices were also used while in hospital. Indomethacin 75 mg daily was given for five days to prevent heterotopic ossification.

    Gait/limb loading until full loading: Heel to flat foot weight bearing for four weeks followed by progression to full weight bearing. A continuous passive motion device was also provided for six weeks for 4–6 h a day from 0 to 90 degrees of hip flexion.

     

  11. Follow-Up and Complications

     

    Report of postoperative complications and their management (i.e., recurrent dislocation): The patient complained of symptomatic hardware at the greater trochanter osteotomy site. Therefore, the two screws were removed four months after the index operation.

     

  12. Discussion

     

    Advantages of the applied method: Surgical hip dislocation is a reliable and versatile surgical option for several intra-articular, and extra-articular hip pathologies such as femoroacetabular impingement, labral tears, excision of benign tumors, unstable slipped capital femoral epiphyses, femoral head fractures, femoral head chondral defects, some acetabular fractures, and post-Perthes disease. There are several advantages to this approach which include the ability to visualize the entire femoral head and acetabulum as well as the ability to address

     

    both intra-articular and extra-articular pathologies at once. When compared to hip arthroscopy, it does not require a traction table which has its risks, and there may be a lower risk of chondral injury [40].

    Disadvantages of the method: The biggest disadvantage to the surgical hip dislocation is likely the trochanteric osteotomy. Retained hardware can lead to pain postoperatively and require removal of hardware. There is also a larger dissection compared to hip arthroscopy and delays in the rehabilitation of the hip abductors. Its most common complication is heterotopic ossification [23]. The larger dissection may also be a cosmetic concern to patients. Furthermore, it may be more difficult to appreciate smaller labral tears as compared to hip arthroscopy.

    Alternative evidence-based techniques for the case: Hip arthroscopy.

    Why is the chosen technique better for this case? Surgical hip dislocation allowed for full visualization of the acetabulum and femoral head to precisely address the large area of posterior acetabular overcoverage. It also provided the ability to perform a labral reconstruction with a fascia lata autograft.

    Indications and contraindications for your technique: Indications: intra-articular and extra-articular causes for femoroacetabular impingement, excision of benign tumors (synovial chondromatosis, pigmented villonodular synovitis, osteoid osteoma, exostosis, etc), some acetabulum fractures, femoral head fractures, femoral head osteochondral defects, unstable slipped capital femoral epiphyses, and post-Perthes disease. Contraindications: evidence of osteoarthritis in the setting of femoroacetabular impingement or post-Perthes disease and patients with a retro-verted acetabulum and a deficient posterior wall. While not an absolute contraindication, it is becoming increasingly evident that patients over the age of 40 years have less predictable outcomes with surgical hip dislocations for femoroacetabular impingement [41].

    Learning curve and how to manage complications: In experienced hands, the surgical hip

    dislocation is a safe procedure with a low complication rate. The learning curve for this procedure is high, but it may not be as long as that for hip arthroscopy. The most important component to learning the surgical hip dislocation is knowing and understanding femoral head vascularity. One of the most feared complications of this approach is femoral head osteonecrosis, but this is rare. Failure to understand and protect the ascending branch of the medial femoral circumflex artery as well as the posterosuperior retinacular vessels may lead to femoral head osteonecrosis. Therefore, it is paramount that the surgeon performs the osteotomy well and recognizes the need to protect the quadratus femoris muscle during dissection and master the Z-shaped capsulotomy. Other complications include neurologic injury to the sciatic nerve which is usually a neurapraxia and transient, heterotopic ossification, symptomatic hardware, and greater trochanteric nonunion. Sciatic nerve neurapraxia is usually treated with observation, foot drop splints, and physiotherapy. Heterotopic ossification can be prevented with the use of medical prophylaxis, such as indomethacin. Symptomatic hardware is treated with removal of hardware.

    Level of evidence concerning the superiority

    of this method against others: Level IV.

    There are currently no high-level studies comparing arthroscopy versus surgical hip dislocation in the treatment of hip pathology. A new systematic review on the mid- to longterm follow-up of arthroscopic versus open surgical treatment of femoroacetabular impingement did not find any high-level studies [30]. They concluded that both procedures maintained the same survival rates. Furthermore, both procedures had the same clinical outcomes scores except for the 12-Item Short-Form Survey (SF-12) which was superior with arthroscopy. A recent study demonstrated that 80% of patients treated for femoroacetabular impingement with a surgical hip dislocation at a minimum of 10 years of follow-up maintained good clinical outcomes and had no osteoarthritis progression [42].