Philippe Gillet

The fate of the adjacent motion segments after lumbar fusion.

Lumbar spine fusion is a commonly performed procedure in various pathologic conditions of the spine. Its role remains debated, and moreover, delayed complications may occur, among which is transitional segment alteration leading to recurrence of back pain, gross instability, and neurologic symptoms. Little is known about the long-term prevalence of this complication because of a lack of specific studies. We analyzed the fate of the transitional segments in a homogeneous group of patients operated on during a 14-year period for degenerative conditions of the lumbar spine resistant to conservative treatment. Follow-up ranged from 2 to 15 years. Seventy-five percent of our study group had a minimal 5-year follow-up. In this subgroup, 41% of the patients developed transitional segment alterations, and 20% needed a secondary operation for extension of the fusion. Potential risk factors such as postoperative delay, length of fusion, and spine imbalance were recognized. The frequency of delayed alterations of the adjacent segment and the severity of symptoms related to this complication in this study raise questions about the justification of fusion procedures in degenerative conditions of the spine without threatening instability. Data from the literature confirm the severity of the problem, but many uncertainties remain because of the lack of homogeneous and complete data on both the normal evolution of motion segments of the lumbar spine with age and the fate of the same segments when transformed in transitional segments. Future prospective studies on the subject are needed and must deal with homogeneous groups of patients. More reconstructive surgical procedures need to be developed to lessen the need for fusion procedures.

Midterm Results with a Bipolar Radial Head Prosthesis: Radiographic Evidence of Loosening at the Bone-Cement Interface

BACKGROUNDnMetal prostheses are useful for restoring elbow and forearm stability when the radial head cannot be fixed after a fracture. Because the anatomy of the radial head is difficult to reproduce with a prosthesis, two different options have been proposed: a bipolar prosthesis with a fixed stem and a mobile head, and a monoblock prosthesis with a smooth stem that is intentionally fixed loosely in the neck of the radius. One concern with a fixed-stem implant with a mobile head has been the risk of osteolysis. The purpose of this study was to evaluate radiographic changes reflecting or suggesting progressive osteolysis in patients with a bipolar radial head prosthesis.nnnMETHODSnThe functional and radiographic outcomes following treatment of fifty-one comminuted fractures of the radial head with a bipolar radial head prosthesis in fifty-one consecutive patients were evaluated at a mean of 8.4 years postoperatively. There were eleven isolated comminuted fractures involving the entire radial head. Thirty-four fractures were associated with a posterior elbow dislocation, and six patients had a posterior Monteggia lesion.nnnRESULTSnAccording to the Mayo Elbow Performance Index, fourteen elbows were graded as excellent; twenty-five, as good; nine, as fair; and three, as poor. Radiographic changes reflecting or suggesting progressive osteolysis were present in thirty-seven patients. Complications occurred in ten patients, but only one underwent surgical treatment, for an ulnar neuropathy.nnnCONCLUSIONSnAlthough satisfactory midterm functional results were achieved in thirty-nine of the fifty-one patients, the high prevalence of adverse radiographic changes suggesting periprosthetic osteolysis should alert clinicians to this possible drawback of the use of bipolar radial head prostheses, especially in young and/or active patients.

Direct repair of spondylolysis without spondylolisthesis, using a rod-screw construct and bone grafting of the pars defect.

STUDY DESIGNnA retrospective study of patient outcome after pars repair using an original technique in patients with spondylolysis without spondylolisthesis and degenerative disk disease.nnnOBJECTIVESnTo assess the results of a new technique of internal fixation that avoids penetration of the spinal canal, temporary fixation of the lumbosacral junction, and postoperative bracing owing to stable instrumentation consisting of pedicle screws and a V-shaped rod resting against the inferior aspect on the spinous process and the posterior aspects of the laminas.nnnSUMMARY OF BACKGROUND DATAnPreviously described techniques for direct repair of a pars defect often require postoperative bracing and can require intracanal penetration of wires or hooks; screws passing directly through the defect, thereby lessening the bone surface available for bone grafting; and temporary fixation of the lumbosacral junction with a plate that must be removed.nnnMETHODSnPatients with painful pars defect not responding to conservative therapy and interfering with everyday life, sports, or work were considered to be eligible for direct repair of the spondylolysis rather than lumbosacral fusion, if there was no associated degenerative disk disease or spondylolisthesis. The surgical technique involves placement of screws on the pedicles of the involved vertebra and the fixation of the loose posterior arch with a solid rod bent in a V shape, taking purchase on the spinous process and laminas. A bone graft is placed under compression in the pars defect before the rod-screw construct is tightened.nnnRESULTSnThe first 10 patients who underwent this technique had an average follow-up of 35 months (range, 7 months to 5.3 years); mean age at operation was 26 years (range, 16-48 years). Six patients had an excellent result, returned to normal everyday life and work, and participated in sports when desired. The outcome in one patient was rated good and in one, fair. The procedure in one was considered a failure, although bone fusion seemed to have been obtained. Seven patients would recommend the operation, one would hesitate. No complications were encountered because of the specific design of the construct.nnnCONCLUSIONSnThis new technique offers the advantage of being easy and fast, it can be performed using a great number of available spinal instrumentations using rods and pedicle screws. There is no violation of the neural canal except in the case of a misplacement of pedicle screws. No postoperative brace was used, return to everyday life avoiding low back stress was immediate, and return to work or sports was possible 3 to 6 months after the procedure. This technique seems safe and effective but needs careful selection of patients, as do all other techniques for direct repair of pars interarticularis.

Health-related quality of life after total knee or hip replacement for osteoarthritis: a 7-year prospective study

ObjectiveTo assess health-related quality of life (HRQOL) in a prospective study with 7xa0years of follow-up in 49 consecutive patients who underwent a total joint replacement because of osteoarthritis.MethodsGeneric HRQOL was assessed with the short-form 36 (SF-36) and specific HRQOL with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC).ResultsOut of the 39 subjects who have completed the 7xa0years of follow-up of this study, 22 (56.4xa0%) underwent a hip replacement surgery and the other 17 (43.6xa0%) a knee replacement. Six months after surgery, a significant improvement, compared to preoperative scores, was observed in two of the eight dimensions of the SF-36 (i.e. physical function and pain). The same dimensions, pain and physical function, at the same time, 6xa0months after surgery, measured by the WOMAC, showed a significant improvement as well, but there was no significant change in the stiffness score. From 6xa0months to the end of follow-up, changes in SF-36 scores showed a significant improvement in physical function (pxa0=xa00.008), role-physical (pxa0=xa00.004) and role-emotional (pxa0=xa00.01) while all scores of the WOMAC improved (pxa0<xa00.001 for pain, pxa0<xa00.001 for stiffness and pxa0<xa00.01 for physical function).ConclusionThe improvements observed in HRQOL at short term after surgery, are at least maintained over a 7-year follow-up period.

15-deoxy-delta12,14-prostaglandin J2 inhibits Bay 11-7085-induced sustained extracellular signal-regulated kinase phosphorylation and apoptosis in human articular chondrocytes and synovial fibroblasts

We have previously shown that nuclear factor-κB inhibition by adenovirus expressing mutated IκB-α or by proteasome inhibitor increases human articular chondrocytes sensibility to apoptosis. Moreover, the nuclear factor-κB inhibitor BAY11-7085, a potent anti-inflammatory drug in rat adjuvant arthritis, is itself a proapoptotic agent for chondrocytes. In this work, we show that BAY 11-7085 but not the proteasome inhibitor MG-132 induced a rapid and sustained phosphorylation of extracellular signal-regulated kinases (ERK1/2) in human articular chondrocytes. The level of ERK1/2 phosphorylation correlated with BAY 11-7085 concentration and chondrocyte apoptosis. 15-Deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) and its precursor prostaglandin (PG) D2 but not PGE2 and PGF2α rescued chondrocytes from BAY 11-7085-induced apoptosis. 15d-PGJ2 markedly inhibited BAY 11-7085-induced phosphorylation of ERK1/2. BAY 11-7085 also induced ERK1/2 phosphorylation and apoptosis in human synovial fibroblasts, and these reactions were down-regulated by 15d-PGJ2. Further analysis in synovial fibroblasts showed that only molecules that suppressed BAY 11-7085-induced phosphorylation of ERK1/2 (i.e. 15d-PGJ2, PGD2, and to a lesser extent, MEK1/2 inhibitor UO126, but not prostaglandins E2 and F2α or peroxisome proliferator-activated receptor-γ agonist ciglitazone) were able protect cells from apoptosis. These results suggested that the antiapoptotic effect of 15d-PGJ2 on chondrocytes and synovial fibroblasts might involve inhibition of ERK1/2 phosphorylation.

Comparison of gaseous cryotherapy with more traditional forms of cryotherapy following total knee arthroplasty.

OBJECTIVEnThe aim of this study was to assess the efficacy of gaseous cryotherapy following total knee arthroplasty (TKA) and to compare it to routinely used strategies for applying cold therapy.nnnPATIENTS AND METHODSnSixty-six patients undergoing primary unilateral TKA were randomized into three groups and received gaseous cryotherapy (GC), cold pack and cryocuff applications, respectively throughout the hospital stay. Primary outcomes (knee pain intensity, mobility and girth measurements) were recorded on preoperative day 1 as well as on postoperative day (POD) 7. Cutaneous temperature of the knee sides were also measured on POD7 just before and immediately after cold application.nnnRESULTSnAlthough skin temperature dropped to 14°C following GC versus 22 to 24°C for the other two applications (P<0,05), the three groups did not differ at POD7 regarding the three primary outcomes. No adverse effects were observed with any of the ways of application.nnnCONCLUSIONSnGaseous cryotherapy was not more beneficial than routinely used strategies for applying cold therapy. Further studies with larger sample size and with a more frequent and closer gaseous cryotherapy applications are needed to confirm our results.

Peroxisome proliferator-activated receptor-gamma1 is dephosphorylated and degraded during BAY 11-7085-induced synovial fibroblast apoptosis.

Peroxisome proliferator-activated receptor-γ (PPAR-γ) plays a central role in whole body metabolism by regulating adipocyte differentiation and energy storage. Recently, however, PPAR-γ has also been demonstrated to affect proliferation, differentiation, and apoptosis of different cell types. As we have previously shown that BAY 11-7085-induced synovial fibroblast apoptosis is prevented by PPAR-γ agonist 15d-PGJ2; the expression of PPAR-γ in these cells was studied. Both PPAR-γ1 and PPAR-γ2 isoforms were cloned from synovial fibroblast RNA, but only PPAR-γ1 was detected by Western blot, showing constitutive nuclear expression. Within minutes of BAY 11-7085 treatment, a PPAR-γ1-specific band was shifted into a form of higher mobility, suggesting dephosphorylation, as confirmed by phosphatase treatment of cell extracts. Of interest, BAY 11-7085-induced PPAR-γ1 dephosphorylation was followed by PARP and caspase-8 cleavage as well as by PPAR-γ1 protein degradation. PPAR-γ1 dephosphorylation was followed by the loss of PPAR-DNA binding activity ubiquitously present in synovial fibroblast nuclear extracts. Unlike the phosphorylated form, dephosphorylated PPAR-γ1 was found in insoluble membrane cell fraction and was not ubiquitinated before degradation. PPAR-γ1 dephosphorylation coincided with ERK1/2 phosphorylation that accompanies BAY 11-7085-induced synovial fibroblasts apoptosis. 15d-PGJ2, PGD2, and partially UO126, down-regulated ERK1/2 phosphorylation, protected cells from BAY 11-7085-induced apoptosis, and reversed both PPAR-γ dephosphorylation and degradation. Furthermore, PPAR-γ antagonist BADGE induced PPAR-γ1 degradation, ERK1/2 phosphorylation, and synovial fibroblasts apoptosis. The results presented suggest an anti-apoptotic role for PPAR-γ1 in synovial fibroblasts. Since apoptotic marker PARP is cleaved after PPAR-γ1 dephosphorylation but before PPAR-γ1 degradation, dephosphorylation event might be enough to mediate BAY 11-7085-induced apoptosis in synovial fibroblasts.

Restriction of spontaneous and prednisolone-induced leptin production to dedifferentiated state in human hip OA chondrocytes: role of Smad1 and β-catenin activation

OBJECTIVEnThe aetiology of OA is not fully understood although several adipokines such as leptin are known mediators of disease progression. Since leptin levels were increased in synovial fluid compared to serum in OA patients, it was suggested that joint cells themselves could produce leptin. However, exact mechanisms underlying leptin production by chondrocytes are poorly understood. Nevertheless, prednisolone, although displaying powerful anti-inflammatory properties has been recently reported to be potent stimulator of leptin and its receptor in OA synovial fibroblasts. Therefore, we investigated, inxa0vitro, spontaneous and prednisolone-induced leptin production in OA chondrocytes, focusing on transforming growth factor-β (TGFβ) and Wnt/β-catenin pathways.nnnDESIGNnWe used an inxa0vitro dedifferentiation model, comparing human freshly isolated hip OA chondrocytes cultivated in monolayer during 1 day (type II, COL2A1xa0+; type X, COL10A1xa0+ and type I collagen, COL1A1 -) or 14 days (COL2A1 -; COL10A1xa0- and COL1A1+).nnnRESULTSnLeptin expression was not detected in day1 OA chondrocytes whereas day14 OA chondrocytes produced leptin, significantly increased with prednisolone. Activin receptor-like kinase 1 (ALK1)/ALK5 ratio was shifted during dedifferentiation, from high ALK5 and phospho (p)-Smad2 expression at day1 to high ALK1, endoglin and p-Smad1/5 expression at day14. Moreover, inactive glycogen synthase kinase 3 (GSK3) and active β-catenin were only found in dedifferentiated OA chondrocytes. Smad1 and β-catenin but not endoglin stable lentiviral silencing led to a significant decrease in leptin production by dedifferentiated OA chondrocytes.nnnCONCLUSIONSnOnly dedifferentiated OA chondrocytes produced leptin. Prednisolone markedly enhanced leptin production, which involved Smad1 and β-catenin activation.

Repérage scintigraphique peropératoire d’une métastase costale unique d’un adénocarcinome prostatique opéré

We present a case of a lonely bone lesion after a prostatic adenocarcinoma with recurrent increased PSA. The localization of the metastasis at the level of a rib is infrequent. The precise localization of the lesion was made possible by intraoperative scintigraphy. Histology confirmed the complete resection of the lesion with safe margins.

Comment on: Long term actuarial survivorship analysis of an interspinous stabilization system (J Senegas et al.)

This paper evaluates the survivorship of interspinous implants implanted in association with a decompression procedure of the lumbar spine, either discectomy or fenestration, at a mean 14-years’ follow-up. It gives important information about the safety of the procedure concerning possible short and long-term complications linked to the device itself. It is also noteworthy that only 10% of the patients secondarily needed adjacent-level surgery. n nHowever, this study has a number of shortcomings. n nOnly 59% of the patients were available for follow-up and the information about removal of the device or other subsequent operation at the operated or at an adjacent level was obtained through a telephone interview, information being obtained through close relatives in the case of patient’s death. It is common in daily practice to observe that patients do not always fully understand the nature of an operation they undergo, if the information about the removal or not of the implant is probably reliable the exact nature of another surgical procedure and the level of this procedure may be questioned. n nThe authors state that patients who underwent the placement of an interspinous implant would have been scheduled for a fusion in association with the decompression procedure, the indication being instability or associated low back pain. They report outcomes at least equal to those of fusion, which is understood by the reader as clinical outcome, including at least partial relief of low back pain if present initially. On two occasions, the notion of outcome in the text clearly not only relates to survival of the implants. However, there is very little information on the clinical status of the patients preoperatively and at last follow-up regarding low back pain. Even regarding the preservation of stability at the instrumented level, outcome assessment should include systematic preoperative, postoperative and long-term follow-up radiographs, ideally with dynamic views. The long-term preservation or restoration of sagittal lumbar alignment would have interestingly been documented by radiographs in a significant number of patients. n nRegarding the rate of reoperation at long term for adjacent level problems, a 10% rate is encouraging; however, it must be balanced with another 11% reoperation rate at the level of the index procedure, which is probably a much higher reoperation rate than after fusion. Overall, the need for another operation, at the same level or at an adjacent level, does not appear to be very different than after initial fusion; however, a number of secondary operations could have been less invasive than after fusion procedures. n nIn conclusion, I believe this paper gives important information about the safety of implanting an interspinous device of the Wallis type, about the absence of significant complications related to the implant and the technique themselves, but it gives no undebatable information on the indications to associate such a procedure with a decompression operation, neither does it permit to truly compare the result on low back pain after a fusion. The indication of a stabilisation procedure when performing a discectomy or a laminectomy remains a matter of debate; the safety of an interspinous implant when compared to an instrumented fusion does not allow the surgeon to supplement his indications for an associated stabilisation procedure in these circumstances. Moreover the results of this paper certainly do not support the indication of using such a device to treat low back pain per se. n nTo perfectly ascertain the pertinence of interspinous devices, randomised prospective studies comparing patients with decompression alone, decompression with dynamic stabilisation and decompression with fusion (posterior or interbody?), are required.