Clinical significance of muscular deep-vein thrombosis after total knee arthroplasty.

BACKGROUND The definition of gastrocneumus and soleus deep-vein thrombosis (DVT) remains controversial. The purpose of this study was to evaluate the clinical significance of muscular deep-vein thrombosis after total knee arthroplasty (TKA). METHODS This study consisted of 359 consecutive patients undergoing TKA evaluated for DVT by ascending venography. Venographies were performed 5 to 7 days after surgery. Those patients showing positive DVT underwent a follow-up venographic study at 3 months. The evaluation parameters included clinical symptoms, late DVT, thrombus propagation and pulmonary embolism. The data from patients with isolated muscular DVT were compared statistically with those patients with DVT of the leg veins and combined DVT. RESULTS Of 359 patients, 175 (49%) developed venographic DVT including 160 with distal and 15 with proximal DVT. Of the 160 cases with distal DVT, 83 (52%) involved the gastroneumus and soleus muscular veins. Of these 83 cases, 38 (46%) were isolated muscular DVT and 45 (54%) involved muscular branches and major leg veins including the anterior and posterior tibial and peroneal veins. Patients with isolated muscular DVT showed comparable rates of clinical symptoms, late DVT, thrombus propagation and no pulmonary embolism compared with patients with DVT in the major leg veins (p = 0.874, 0.398 and 1.000) and patients with combined DVT (p = 0.155, 0.592 and 1.000). CONCLUSION The clinical significance of isolated muscular DVT is comparable to that of the major leg veins and combined DVT. Muscular DVT in the calf is considered a significant clinical entity and should be treated accordingly.