Advertisement for orthosearch.org.uk
Results 1 - 3 of 3
Results per page:
Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_III | Pages 215 - 215
1 Nov 2002
Shen W Shen Y
Full Access

Introduction: The nonunion rate is higher and loss of reduction is common after reduction and fusion for the higher grades of spondylolisthesis. This is due to fusion bone base deficiency and lack of anterior column support, and can be addressed by supplementing the posterolateral fusion with a posterior lumbar interbody fusion (PLIF).

Materials: All patients had a single disc level degenerative or spondylolytic slip exceeding 25%. Laminectomy and instrumented reduction (VSP or TSRH) was performed. 86 patients underwent posterolateral fusion and 82 underwent the same procedure plus a PLIF (done by tightly impacting bone chips into the disc cavity after a very aggressive discectomy). No fusion cages were used.

Results: Presented as No-PLIF vs. PLIF. Age: 56 vs. 52 years. Male/Female: 14:72 vs. 15:67. Cases with pars fx: 44% vs. 56%. Level of slip (L3-4, L4-5, L5-S1): 9, 59, 18 vs. 4, 60, 18. Iatrogenic neurological injury: none vs. none. Deep infection: 1 vs. none. Nonunion: 9.3% vs. 2.4%. Broken screws: 6 vs. 2. Degree of slip (pre-op to post-op to 2 years): 34% to 11% to 20% vs. 38% to 4% to 8%. Patients that lost reduction: 67% vs. 18%. Disc height gained at 2 years: −0.2 mm vs. 2.3 mm. Subjective back pain score: 3.5 vs. 2.0. Greenough LBOS score: 54 vs. 62. Patients very satisfied: 43% vs. 60%. Cases with adjacent level slip: 4 vs. 4.

Discussion: Spondylolisthesis is commonly treated with a spinal fusion. The goal of surgery is to eliminate motion between the unstable segments, and mechanically it is preferable that the vertebrae fuse in as near anatomic position as possible. It has been shown that the fusion rate decreases with higher degrees of slip, with the spondylolytic types, and with severely degenerated discs. Pedicle screw instrumentation can increase the fusion rate. Reduction of the slip can often be achieved, but it is common to lose the reduction over the course of 1–2 years if only posterolateral fusion is done. Adding an interbody fusion cage can help restore the disc height and widen the intervertebral foramen, but increases complexity, cost, and may actually decrease bone contact area and compression forces. We have found that in grade II and worse slips, pedicle screw fixation alone is not strong enough to maintain reduction of either vertebral alignment or disc height. Adding a chip PLIF appears safe and effective in increasing the union rate and the disc height, and in maintaining reduction in grade II spondylolisthesis. Clinical results are better, the infection rate is not higher. In our hands, there have been no neurological injuries. This study also raises questions about the role and need for interbody fusion cages.


The Journal of Bone & Joint Surgery British Volume
Vol. 79-B, Issue 4 | Pages 680 - 683
1 Jul 1997
Kumar VP Satku K Liu J Shen Y

We studied the origin of the anterior deltoid from the lateral third of the clavicle and the leading anterior edge of the acromion in 18 cadaver shoulders by anatomical and histological methods.

The main origin of the deltoid was from the superior surface of the anterior acromion, but muscle and tendinous attachments were also seen on the entire anterior surface of the acromion, its anteroinferior surface and on the whole width of the anterior surface of the clavicle.

Mock arthroscopic acromioplasty was shown to detach deltoid fibres from the anterior surfaces, leaving the superior attachment in continuity. Potentially, arthroscopic subacromial and clavicular resection can detach deltoid fibres originating from the anterior and anteroinferior surfaces of the acromion and clavicle and thus weaken the anterior deltoid.


The Journal of Bone & Joint Surgery British Volume
Vol. 57-B, Issue 4 | Pages 463 - 465
1 Nov 1975
Shen Y

Nine cases of abduction contracture of the hip in children from contracture of the gluteus maximus muscle are reported. Division of the aponeurosis gluteus maximus over the greater trochanter always permitted full adduction.