In situ pinning with arthroscopic osteoplasty for mild SCFE: A preliminary technical report

Abstract

Background: There is emerging evidence that even mild slipped capital femoral epiphysis leads to early articular damage. Therefore, we have begun treating patients with mild slips and signs of impingement with in situ pinning and immediate arthroscopic osteoplasty. DESCRIPTION OF TECHNIQUES: Surgery was performed using the fracture table. After in situ pinning and diagnostic arthroscopy, peripheral compartment access was obtained and head-neck osteoplasty was completed.

Methods: Between March 2008 and August 2009, three male patients (age range, 11-15 years; BMI, 22-31 kg/m(2)) presented with slip angles between 15º and 30º. All were ambulatory without assistance but had 2 to 12 weeks of hip and/or knee pain, limited motion and a positive impingement test. Postoperatively, patients were assessed at 6 weeks; 3 and 6 months; then every 6 months for the first two years. Hip motion, epiphyseal-metaphyseal offsets and alpha angles were determined. Patients completed the UCLA activity scale at latest followup that ranged from 6 to 23 months.

Results: Arthroscopic evaluation revealed labral fraying, acetabular chondromalacia, and a prominent metaphyseal ridge. At last followup, each was pain-free and had returned to unrestricted activities. Hip motion improved in all and none demonstrated clinical impingement. Radiographs showed normalized epiphyseal-metaphyseal offsets and alpha angles.

Conclusions: In situ pinning with arthroscopic osteoplasty can limit impingement after mild slipped capital femoral epiphysis. Due to limited followup, we are unable to say whether this protocol reduces subsequent articular damage. Although we recommend performing these procedures concomitantly, they can be performed in a staged fashion, especially since hip arthroscopy following an epiphyseal slip can be challenging.

Fig. 1A–C

Frog-leg lateral radiographs of the hip show posterior tilt and translation of the epiphysis (E) with anterior prominence (*) of the proximal metaphysis (M). (A) Left hip of Patient 2. (B) Epiphyseal-metaphyseal offset of left hip of Patient 2. (C) Alpha angle of left hip of Patient 2. Dashed line = line along center of femoral neck; Line E = line along anterior epiphysis parallel to femoral neck; Line M = line along anterior metaphysis parallel to femoral neck; α = alpha angle.

Fig. 2

Arthroscopic view of the right hip of Patient 1 shows fraying and hyperemia of the anterior labrum (L). Synovitis is present on the articular side of the joint capsule (C). FH = femoral head; AC = acetabular cartilage.

Fig. 3

Arthroscopic view of the right hip of Patient 1 with a probe placed on softened but intact acetabular cartilage (AC). FH = femoral head (FH); L = labrum.

Fig. 4A–B

Arthroscopic view of the anterior head-neck junction shows abrasive prominences (arrows) projecting anteriorly along the band of epiphyseal-metaphyseal separation. (A) Right hip of Patient 1. (B) Left hip of Patient 2. FH = femoral head; M = metaphysis.

Fig. 5

Arthroscopic view of the left hip of Patient 3 shows the anterior separation (S) between the femoral head (FH) and metaphysis (M).

Fig. 6

Arthroscopic view of the left hip of Patient 3 shows resection of the proximal anterior metaphysis (M). Resection is carried proximally to the level of the physis (P). FH = femoral head.

Fig. 7A–C

Frog-leg lateral hip radiographs demonstrate in situ pinning of the epiphysis (E) and head-neck osteoplasty (O). The proximal anterior metaphysis (*) is no longer prominent. (A) Left hip of Patient 2. (B) Corrected epiphyseal-metaphyseal offset of left hip of Patient 2. (C) Corrected alpha angle of the left hip of Patient 2. Dashed line = line along center of femoral neck; Line E = line along anterior epiphysis parallel to femoral neck; Line M = line along anterior metaphysis parallel to femoral neck; α = alpha angle.