Two patients with rotary tiller–related traumatic knee dislocation and multiligament rupture had generally favorable early postoperative outcomes following emergency reduction, vascular assessment, single-stage reconstruction, and structured rehabilitation, according to a case series published in Clinical Case Reports.
The report described 2 male patients, aged 47 and 49 years, who presented within 2 hours of rotary tiller injuries sustained in Southwest China, where the researchers noted agricultural mechanization has increased the incidence of rotary tiller trauma. The researchers also cited epidemiologic data estimating an annual incidence of approximately 15.3 knee dislocations per million people, with young male patients at highest risk.
Both patients had traumatic right knee dislocation with rupture of the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament, and lateral collateral ligament, along with lateral meniscus injury.
The researchers emphasized that traumatic knee dislocation carries a substantial risk of vascular injury, citing prior data showing popliteal artery injury in approximately 16% of traumatic knee dislocations. Both patients underwent radiography, computed tomography, magnetic resonance imaging (MRI), physical neurovascular examination, and ankle-brachial index (ABI) assessment.
Because both patients had palpable dorsalis pedis pulses, normal capillary refill, intact sensation, and ABI values greater than 0.9, computed tomography angiography (CTA) was not performed. Instead, both patients underwent close clinical monitoring for vascular compromise, consistent with current recommendations cited by the researchers. Neither patient developed vascular complications during follow-up.
The researchers noted that closed reduction is feasible in only about 35% of traumatic knee dislocations reported in prior literature, helping explain why both patients required open reduction.
The first patient presented with a rotational knee dislocation with lateral patellar incarceration in the femoral intercondylar notch, requiring emergency open reduction. MRI confirmed rupture of the ACL, PCL, medial collateral ligament, and lateral collateral ligament, as well as lateral meniscus injury and partial patellar tendon and medial patellofemoral ligament injury.
At 2 weeks following injury, after incision healing and edema resolution, the patient underwent single-stage arthroscopic ACL and PCL reconstruction, collateral ligament repair, and lateral meniscus repair. The ACL was reconstructed using autologous semitendinosus, gracilis, and half of the peroneus longus tendons, whereas the PCL was reconstructed using a polyetheretherketone (PEEK)-reinforced artificial tendon.
At 1 month, the patient had knee range of motion from 0° to 110° and a Hospital for Special Surgery (HSS) score of 92. At 6 months, range of motion improved to 0° to 135°, gait normalized, knee stability testing remained negative, and the HSS score improved to 98.
The second patient presented with an open posterior knee dislocation and multiple soft-tissue wounds. Following emergency debridement and reduction, definitive reconstruction was delayed until 4 weeks postinjury because of wound necrosis and 3 recurrent redislocation episodes triggered by what the researchers described as alcohol withdrawal hysteria.
MRI confirmed rupture of the ACL, PCL, medial collateral ligament, and lateral collateral ligament, along with lateral meniscus injury. The patient underwent arthroscopic ACL reconstruction using autologous semitendinosus and gracilis tendons, PCL reconstruction using a PEEK-reinforced artificial tendon, medial patellofemoral ligament reconstruction using gracilis autograft, lateral retinaculum repair, medial collateral ligament repair, and lateral meniscus repair.
At 1 month, the second patient had knee range of motion from 0° to 80° and an HSS score of 80, although anterior and posterior drawer testing and varus and valgus stress testing were negative.
The researchers noted that patellofemoral instability requiring medial patellofemoral ligament reconstruction is “often overlooked” in multiligament knee injuries but may be important for functional recovery.
Both patients underwent structured rehabilitation with early controlled mobilization to reduce arthrofibrosis risk. Rehabilitation timelines differed because of surgical timing and soft-tissue condition. The first patient began passive range-of-motion exercises on postoperative day 3 and progressed to full weight-bearing by 6 weeks, whereas the second patient began passive motion on postoperative day 4 and progressed to full weight-bearing by 8 weeks.
The researchers advocated for single-stage reconstruction once soft-tissue conditions improved, noting that this approach may minimize repeated surgical trauma and reduce the interval between injury and reconstruction.
The researchers also described graft-selection considerations specific to their setting. Autografts were selected over allografts partly because of patient financial constraints and limited institutional availability of allograft tissue.
Although the patient who underwent reconstruction within 3 weeks had better early functional recovery, the researchers acknowledged that the cases differed substantially in injury severity, soft-tissue complications, redislocation episodes, and follow-up duration, making it impossible to determine whether surgical timing independently accounted for the outcome differences.
“Early surgery, when feasible, combined with a structured rehabilitation program emphasizing early motion,” may support favorable functional outcomes in this injury setting, wrote lead study author Fuhang Shuang, of Northeast Yunnan Central Hospital in Zhaotong, China, and colleagues.
Disclosures: The researchers reported no conflicts of interest.
Source: Clinical Case Reports
