Iatrogenic ischiofemoral impingement due to high tibial osteotomy with overvalgization: a case report
Journal of Medical Case Reports volume 16, Article number: 43 (2022)
Open wedge high tibial osteotomy is a standard procedure for frontal realignment. It is indicated in varus knee with reduced mechanical medial proximal tibia angle. Overcorrection producing a mechanical medial proximal tibia angle out of the normal range (85–90°) is not recommended because this would lead to unphysiological joint-line orientation. Osteotomies around the knee also influence the adjacent ankle and hip joints. For the hip, it is known that frontal alignment of the leg influences the ischiofemoral space. A decreased ischiofemoral space can lead to painful impingement between the ischial bone and the lesser trochanter.
A 53-year-old German woman presented with severe ischiofemoral impingement symptoms and valgus malalignment of the left leg after open wedge high tibial osteotomy, which was indicated and performed by an orthopedic surgeon with intention to treat medial knee pain due to degenerative arthritis of the medial compartment years after medial meniscectomy. The mechanical medial proximal tibia angle was 100.5°. We performed closed wedge high tibial osteotomy producing a mechanical medial proximal tibia angle of 90.0° and normal joint-line orientation. The hip pain was gone immediately after the surgery, and the patient had no signs of ischiofemoral impingement or hip pain at last follow-up 12 months after closed wedge high tibial osteotomy.
Frontal realignment osteotomy around the knee can create problems at adjacent joints. Overvalgization of the proximal tibia made the patient compensate by hyperadduction of the hip to enable full foot sole contact with the floor. Hyperadduction of the hip decreased the ischiofemoral space, leading to severe impingement. Therefore, meticulous planning of osteotomies is important not to produce unphysiological situations or unwanted negative effects at the level of an adjacent joint.
Open wedge high tibial osteotomy (owHTO) is a standard procedure for frontal realignment [1, 2]. It is indicated in varus knee with reduced mechanical medial proximal tibia angle (mMPTA) . Overcorrection producing a mMPTA out of the normal range (85–90°) is not recommended because this would lead to unphysiological joint-line orientation [4, 5].
Osteotomies around the knee also influence the adjacent joints—ankle and hip [6,7,8,9]. For the hip, it was demonstrated earlier that frontal alignment of the leg influences the ischiofemoral space , but this has not become common knowledge yet. A decreased ischiofemoral space can lead to impingement between the ischial bone and the lesser trochanter [7, 9]. This is demonstrated and illustrated by the present case.
Unphysiological valgus knee alignment is normally compensated by the patient by adducting the hip to enable full foot sole contact with the floor . As hip adduction decreases the space between the ischial bone of the pelvis and the lesser trochanter of the femur, ischiofemoral impingement can result . This is known to be an important extraarticular source of hip pain.
A 53-year-old German woman presented with severe ischiofemoral impingement symptoms and valgus malalignment of the left leg after owHTO, which was indicated and performed by an orthopedic surgeon with intention to treat medial knee pain due to degenerative arthritis of the medial compartment years after medial meniscectomy. The initial osteotomy was performed 4 years previously, and the patient has been severely symptomatic since this surgery.
On clinical examination, the Faber test was positive and external rotation of the hip in extension was painful, too. Radiologically, the mMPTA was 101.5° (Fig. 1a). The patient almost could not walk because she needed to adduct her left hip so much to enable her foot to approach the floor evenly. With a positive Faber test, psoas sign, and posterior impingement test, the range of motion (ROM) of the affected hip was Ext/Flex 0/0/120°, Abd/Add 45/0/0°, Aro/Iro 40/0/15°. The WOMAC score was 20.3. The Merle D’Aubigné and Postel score was 13. Torsional malalignment was excluded by torsional CT analysis. On axial CT slides, a reduced ischiofemoral distance was found on the affected left side (Fig. 2).
We planned (Fig. 1a, b) and performed cwHTO producing a mMPTA of 90.0° and normal joint-line orientation (Fig. 3). The hip pain was gone immediately after surgery, and the patient had no signs of ischiofemoral impingement or hip pain at the last follow-up 12 months after cwHTO. At this time, the ROM was Ext/Flex 10/0/120°, Abd/Add 45/0/25°, Aro/Iro 45/0/20°. The WOMAC score was 87.5, and the Merle D’Aubigné and Postel score was 18.
Discussion and conclusions
In the presented case of a 53-year-old patient, massive overvalgization of about 10° deteriorated the function of the lower extremity tremendously. In varus situations of the knee due to medial joint space narrowing without bony malalignment per se, one should be cautious when performing realignment osteotomies. In these cases, medial unicompartmental knee arthroplasty might be more appropriate.
For sufficient preoperative planning, it is recommended to at least analyze the long-leg axis, the joint-line convergence angle (JLCA), and the following bony angles around the knee on a standardized long-leg standing radiograph: mechanical lateral distal femur angle (mLDFA) and mMPTA [10,11,12]. Figure 1 shows the computer-aided digital planning, which was conducted preoperatively.
Slight overvalgization is accepted in cases with medial gonarthritis, but no unphysiological bony angles or oblique JLCA should be created. To avoid this, often double-level osteotomy of the proximal tibia and the distal femur is indicated in cases with bony malalignment [4, 13, 14]. It was demonstrated earlier that joint-line obliquity (JLO) of more than 3° is associated with worse clinical outcomes after medial owHTO . Overcorrection of more than 3° should be avoided .
In conclusion, frontal realignment osteotomy around the knee can create problems at the hip. Overvalgization of the proximal tibia made the patient compensate by hyperadduction of the hip to enable full foot sole contact with the floor. Hyperadduction of the hip decreased the ischiofemoral space, leading to severely painful symptoms of ischiofemoral impingement. Therefore, meticulous planning of osteotomies according to the described principles is important to avoid unphysiological situations or unwanted negative effects at the knee or the level of an adjacent joint.
Availability of data and materials
The datasets used and analyzed are available from the corresponding author on reasonable request.
High tibial osteotomy
Joint-line convergence angle
Mechanical lateral distal femur angle
Mechanical medial proximal tibia angle
Range of motion
Western Ontario and McMaster Universities Osteoarthritis
Staubli AE, De Simoni C, Babst R, Lobenhoffer P. TomoFix: a new LCP-concept for open wedge osteotomy of the medial proximal tibia. Injury. 2003;34(Suppl 2):B55-62.
Agneskirchner JD, Hurschler C, Wrann CD, Lobenhoffer P. The effects of valgus medial opening wedge high tibial osteotomy on articular cartilage pressure of the knee: a biomechanical study. Arthroscopy. 2007;23(8):852–61.
Schröter S, Mueller J, van Heerwaarden R, Lobenhoffer P, Stöckle U, Albrecht D. Return to work and clinical outcome after open wedge HTO. Knee Surg Sports Traumatol Arthrosc. 2013;21(1):213–9.
Feucht MJ, Winkler PW, Mehl J, Bode G, Forkel P, Imhoff AB, Lutz PM. Isolated high tibial osteotomy is appropriate in less than two-thirds of varus knees if excessive overcorrection of the medial proximal tibial angle should be avoided. Knee Surg Sports Traumatol Arthrosc. 2020. https://doi.org/10.1007/s00167-020-06166-3.
Iseki T, Onishi S, Kanto M, Kanto R, Kambara S, Yoshiya S, Tachibana T, Nakayama H. Double-level osteotomy for severe varus osteoarthritic knees can prevent change in leg length and restore physiological joint geometry. Knee. 2021;31:136–43.
Konrads C, Ahrend MD, Beyer MR, Stöckle U, Ahmad SS. Supracondylar rotation osteotomy of the femur influences the coronal alignment of the ankle. J Exp Orthop. 2021;8(1):32.
Konrads C, Ahrend MD, Beyer MR, Stöckle U, Ahmad SS. Rotation osteotomy of the distal femur influences coronal femoral alignment and the ischiofemoral space. Arch Orthop Trauma Surg. 2021. https://doi.org/10.1007/s00402-020-03704-z.
Konrads C, Eis A, Ahmad SS, Stöckle U, Döbele S. Osteotomies around the knee lead to corresponding frontal realignment of the ankle. Eur J Orthop Surg Traumatol. 2021. https://doi.org/10.1007/s00590-021-03016-x.
Ahmad SS, Konrads C, Stöckle U, Ahrend MD. The ischiofemoral space of the hip is influenced by the frontal knee alignment. Knee Surg Sports Traumatol Arthrosc. 2021;29(8):2446–52.
Schröter S, Elson DW, Ateschrang A, Ihle C, Stöckle U, Dickschas J, Harrer J. Lower limb deformity analysis and the planning of an osteotomy. J Knee Surg. 2017;30(5):393–408.
Na YG, Lee BK, Choi JU, Lee BH, Sim JA. Change of joint-line convergence angle should be considered for accurate alignment correction in high tibial osteotomy. Knee Surg Relat Res. 2021;33(1):4.
Park JG, Bin SI, Kim JM, Lee BS. Using the lower limb adduction angle to predict postoperative knee joint-line obliquity after open-wedge high tibial osteotomy. Ortho J Sports Med. 2021;9(5):23259671211003990.
Sohn S, Koh IJ, Kim MS, In Y. Risk factors and preventive strategy for excessive coronal inclination of tibial plateau following medial opening-wedge high tibial osteotomy. Arch Orthop Traum Surg. 2021. https://doi.org/10.1007/s00402-020-03660-8.
Akamatsu Y, Nejima S, Tsuji M, Kobayashi H, Muramatsu S. Joint line obliquity was maintained after double-level osteotomy, but was increased after open-wedge high tibial osteotomy. Knee Surg Sports Traumatol Arthrosc. 2021. https://doi.org/10.1007/s00167-020-06430-6.
Song JH, Bin SI, Kim JM, Lee BS. What is an acceptable limit of joint-line obliquity after medial open wedge gith tibial osteotomy? Analysis based on midterm results. Am J Sports Med. 2020;48(12):3028–35.
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Konrads, C., Ahmad, S.S., Histing, T. et al. Iatrogenic ischiofemoral impingement due to high tibial osteotomy with overvalgization: a case report. J Med Case Reports 16, 43 (2022). https://doi.org/10.1186/s13256-022-03257-2