Objective:To evaluate the clinical efficacy of the modified medial gastrocnemius myocutaneous flap (MGMF) with extended anterior, posterior and (or) inferior boundaries.Methods:From January 2002 to September 2022, modified MGMFs were applied onto 33 patients who received reconstructive surgery for soft-tissue defects around knee or in calf, in the Department of Orthopaedics, the Second Xiangya Hospital of Central South University. The size of defects ranged from 10 cm×4 cm to 22 cm×12 cm, and the flap size ranged from 15 cm×6 cm to 28 cm×14 cm. Twenty-five patients had the complication of chronic osteomyelitis. The boundaries of a modified MGMF were as follows: the anterior boundary was the anterior border of the tibia, where the posterior boundary at 3.0 cm lateral to the posterior midline, the proximal boundary at the popliteal fossa crease, and the distal boundary at the plane 2.0 cm above the tip of medial malleolus. The anterior edge of the modified MGMF was designed running along the medial edge of the defect and its curved extension line. Pretibial skin was equally divided into 9 zones, with the 1st to 9th zones from proximal to distal in sequence. Postoperative routine anti-infection treatment was offered. All patients were included in the postoperative follow-up through outpatient visits, telephone or WeChat interviews. Flap viability and wound healing in both donor and recipient sites were evaluated. Function of the affected limb was assessed using the evaluation criteria established by Punor et al.Results:All patients were included in the follow-up for 1 to 169 (median duration: 9)months. The 33 modified MGMFs included MGMFs with extended boundary of anterior ( n=18), inferior ( n=5), anterior combined with inferior ( n=6), posterior combined with anterior ( n=2), and posterior combined with inferior ( n=2) boundaries. Twenty-nine (87.9%) flaps survived completely. Partial necrosis occurred in 4 flaps(12.1%)(2 flaps with extended anterior boundary and 2 flaps with extended inferior boundary). The anterior margins of 26 flaps (78.7%) with extended anterior boundary alone or in combination with extended inferior or posterior boundary exceeded the medial edge of the tibia by 1.0-4.5 (mean, 2.1) cm, and 3 of them reached the anterior edge of tibia. Fourteen (42.4%) modified MGMFs were used to reconstruct the defects involving 1/3 of distal calf, and the distal ends of these defects were located in the 7th ( n=8) or 8th ( n= 6) zone. All the skin grafts in the donor sites survived. During follow-up, 31 patients (93.9%) showed no sign of infection, and 2 patients (6.1%) who had recurrence of chronic osteomyelitis. Functions of the affected limbs were excellent ( n=25), good ( n=6) and fair ( n=2) by Punor et al. Conclusion:Modified MGMF with extended anterior, posterior and (or) inferior boundaries is clinically feasible. It offers advantages of easier design and operation. It can be used to reconstruct a more distal, wider and larger defect as well as broadens the application of the MGMF.

Objective:To evaluate the clinical efficacy of the modified medial gastrocnemius myocutaneous flap (MGMF) with extended anterior, posterior and (or) inferior boundaries.Methods:From January 2002 to September 2022, modified MGMFs were applied onto 33 patients who received reconstructive surgery for soft-tissue defects around knee or in calf, in the Department of Orthopaedics, the Second Xiangya Hospital of Central South University. The size of defects ranged from 10 cm×4 cm to 22 cm×12 cm, and the flap size ranged from 15 cm×6 cm to 28 cm×14 cm. Twenty-five patients had the complication of chronic osteomyelitis. The boundaries of a modified MGMF were as follows: the anterior boundary was the anterior border of the tibia, where the posterior boundary at 3.0 cm lateral to the posterior midline, the proximal boundary at the popliteal fossa crease, and the distal boundary at the plane 2.0 cm above the tip of medial malleolus. The anterior edge of the modified MGMF was designed running along the medial edge of the defect and its curved extension line. Pretibial skin was equally divided into 9 zones, with the 1st to 9th zones from proximal to distal in sequence. Postoperative routine anti-infection treatment was offered. All patients were included in the postoperative follow-up through outpatient visits, telephone or WeChat interviews. Flap viability and wound healing in both donor and recipient sites were evaluated. Function of the affected limb was assessed using the evaluation criteria established by Punor et al.Results:All patients were included in the follow-up for 1 to 169 (median duration: 9)months. The 33 modified MGMFs included MGMFs with extended boundary of anterior ( n=18), inferior ( n=5), anterior combined with inferior ( n=6), posterior combined with anterior ( n=2), and posterior combined with inferior ( n=2) boundaries. Twenty-nine (87.9%) flaps survived completely. Partial necrosis occurred in 4 flaps(12.1%)(2 flaps with extended anterior boundary and 2 flaps with extended inferior boundary). The anterior margins of 26 flaps (78.7%) with extended anterior boundary alone or in combination with extended inferior or posterior boundary exceeded the medial edge of the tibia by 1.0-4.5 (mean, 2.1) cm, and 3 of them reached the anterior edge of tibia. Fourteen (42.4%) modified MGMFs were used to reconstruct the defects involving 1/3 of distal calf, and the distal ends of these defects were located in the 7th ( n=8) or 8th ( n= 6) zone. All the skin grafts in the donor sites survived. During follow-up, 31 patients (93.9%) showed no sign of infection, and 2 patients (6.1%) who had recurrence of chronic osteomyelitis. Functions of the affected limbs were excellent ( n=25), good ( n=6) and fair ( n=2) by Punor et al. Conclusion:Modified MGMF with extended anterior, posterior and (or) inferior boundaries is clinically feasible. It offers advantages of easier design and operation. It can be used to reconstruct a more distal, wider and larger defect as well as broadens the application of the MGMF.