Tissue structure modification in knee osteoarthritis by use of joint distraction: an open 1-year pilot study

Abstract

BackgroundModification of joint tissue damage is challenging in late-stage osteoarthritis (OA). Few options are available for treating end-stage knee OA other than joint replacement.ObjectivesTo examine whether joint distraction can effectively modify knee joint tissue damage and has the potential to delay prosthesis surgery.Methods20 patients (<60 years) with tibiofemoral OA were treated surgically using joint distraction. Distraction (∼5 mm) was applied for 2 months using an external fixation frame. Tissue structure modification at 1 year of follow-up was evaluated radiographically (joint space width (JSW)), by MRI (segmentation of cartilage morphology) and by biochemical markers of collagen type II turnover, with operators blinded to time points. Clinical improvement was evaluated by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Visual Analogue Scale (VAS) pain score.ResultsRadiography demonstrated an increase in mean and minimum JSW (2.7 to 3.6 mm and 1.0 to 1.9 mm; p<0.05 and <0.01). MRI revealed an increase in cartilage thickness (2.4 to 3.0 mm; p<0.001) and a decrease of denuded bone areas (22% to 5%; p<0.001). Collagen type II levels showed a trend towards increased synthesis (+103%; p<0.06) and decreased breakdown (−11%; p<0.08). The WOMAC index increased from 45 to 77 points, and VAS pain decreased from 73 to 31 mm (both p<0.001).ConclusionsJoint distraction can induce tissue structure modification in knee OA and could result in clinical benefit. No current treatment is able to induce such changes. Larger, longer and randomised studies on joint distraction are warranted.

Knee Joint Distraction as an Alternative Surgical Treatment for Osteoarthritis: Rationale and Design of two Randomized Controlled Trials (vs High Tibial Osteotomy and Total Knee Prosthesis)

“…In comparison with the earlier open uncontrolled trial [43] the duration of distraction was shortened with two weeks (from eight to six weeks) to limit treatment burden. The rationale for this shortening to six weeks was founded by the fact that biomarker-turnover of cartilage and bone tissue increases within the first four to six weeks of KJD, and thereafter stabilizes as observed in the prospective uncontrolled trial.…”

“…With shortening of the distraction period the concern about post-treatment stiffness decreased. In order to further diminish the burden of the patients, a continuous distraction was performed instead of a two weekly interruption for continuous passive motion (CPM) therapy upon temporarily removal of the mono-tubes [43] . In both trials a specified KJD-physiotherapy protocol (based on guidelines for TKP and HTO) was developed to make the whole post-surgical procedure similar for all KJD patients and comparable to HTO and TKP.…”

“…Only one prospective open uncontrolled trial has been performed. Follow-up of the 20 treated patients is reported on at one, two, and five years post-treatment [43,44] (ms under review). Clinical benefit with cartilaginous tissue repair has been demonstrated to sustain for up to five years after treatment in over three-quarter of the patients treated.…”

Immediate Effects of Manual Traction on Radiographically Determined Joint Space Width in the Hip Joint

“…18 Studies involving the ankle and knee joints indicated an increase in JSW after treatment similar to manual traction. 16,17,19 However, in these studies, an external fixator was used to apply traction force. Thus, no studies have evaluated the mechanical effect of manual traction of the hip joint on JSW, although this technique is frequently used.…”

Osteoarthritis: a holistic approach

“…This concept that cartilage catabolism in OA may depend upon weight bearing or joint loading is supported by cartilage regeneration occurring following surgical unloading of human joints. 4 Osteoarthritis in humans represents a heterogeneous pathologic process with many potential therapeutic targets. It is therefore unlikely that a single 'magic bullet' will effectively treat all patients.…”