Centre de formation et physiothérapie de Lutry

30/09/2025

🔗📃Effects of physiotherapeutic interventions for reducing arthrogenic muscle inhibition in chronic ankle instability: a systematic review

■ 📌 Objective of the Review
The article systematically reviewed the effectiveness of various physiotherapeutic interventions for reducing arthrogenic muscle inhibition (AMI)—the inability of a muscle to fully contract after joint injury—in individuals with chronic ankle instability (CAI). CAI is a condition marked by recurrent ankle sprains and neuromuscular deficits.

■ 🔬 Methodology
The review analyzed 13 studies that investigated interventions such as proprioceptive training, manual therapy, taping, cryotherapy, anodal transcranial direct current stimulation (atDCS), electrotherapy, and dry needling.
The primary outcomes measured were changes in spinal and corticospinal excitability, assessed through the H/M ratio and transcranial magnetic stimulation (TMS).

■ 💡 Key Findings on Interventions

➡️ Most Promising Interventions
The review concluded that prolonged balance training, cryotherapy, and atDCS (especially when combined with eccentric exercise) showed the most consistent positive effects on reducing AMI.

➡️ Proprioceptive Training
The duration of the intervention appears crucial. A six-week balance training program significantly improved motoneuron excitability.
In contrast, a short 10-minute session of whole-body vibration (WBV) showed no effect.
A single session of balance training did show reduced inhibition of the motor cortex.

➡️ Cryotherapy (Local Cooling)
Three studies found that applying ice to the ankle improved motoneuron excitability (increased H/M ratio) in the soleus, peroneus longus, and tibialis anterior muscles when participants were lying down.
However, these effects were not observed during weight-bearing (standing) positions.

➡️ Anodal Transcranial Direct Current Stimulation (atDCS)
A four-week program combining atDCS with eccentric exercises for ankle evertors resulted in long-term improvements in corticospinal excitability and coincided with functional improvements.
The group performing only eccentric exercises showed just short-term effects.

➡️ Manual Therapy
The results were mixed. One study reported that distal tibiofibular joint mobilization immediately increased the H/M ratio of the soleus muscle.
However, another study using anterior-to-posterior talar mobilization found no significant changes in neural excitability.

➡️ Taping
Findings were inconsistent. One study found that fibular repositioning tape significantly increased the H/M ratio in the soleus muscle.
Another study using a similar technique reported no changes in neural excitability.

➡️ Electrotherapy
A two-week intervention with transcutaneous electrical nerve stimulation (TENS) improved reflex excitability in the peroneus longus muscle.
However, neuromuscular electrical stimulation (NMES) did not produce similar effects.

➡️ Dry Needling
The single study on this topic found no significant changes in neural excitability after applying dry needling to trigger points in the peroneus longus muscle.

■ 📍 Conclusions and Limitations
The review suggests that certain physiotherapeutic techniques can positively influence neural excitability in individuals with CAI, but the evidence for many is limited.
👉A significant limitation is that most of the included studies had small sample sizes, examined only short-term effects, and used varied methodologies, making direct comparisons difficult.
The authors recommend future research with larger samples, longer intervention periods, and long-term follow-ups to establish more solid evidence.

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⚠️Disclaimer: Sharing a study or a part of it is NOT an endorsement. Please read the original article and evaluate critically.⚠️

Link to Article 👇

30/09/2025

A simple guide to understanding how neurons make neurotransmitters

Your brain has different classes of neurons, each defined by the chemical messenger (neurotransmitter) they release. These transmitters are built from specific precursors using unique enzymes and cofactors.

1️⃣ Cholinergic Neurons (green)

Main transmitter: Acetylcholine (ACh).

Source: Built from acetyl-CoA and choline.

Special enzyme: ChAT (choline acetyltransferase).

🟢 Example: These neurons drive muscle contraction and attention.
2️⃣ GABAergic Neurons (blue)

Main transmitter: GABA (gamma-aminobutyric acid).

Source: Derived from glutamate.

Special enzyme: GAD (glutamate decarboxylase).
🟢 Example: GABA is the brain’s main “calm-down” signal.

3️⃣ Glutamatergic Neurons (orange)
Main transmitter: Glutamate.

Source: Recycled from other cells and stored in vesicles.

🟢 Example: Glutamate is the brain’s main “go” signal for learning and memory.

4️⃣ Serotonergic Neurons (green-teal)

Main transmitter: Serotonin (5-HT).
Source: Made from tryptophan → 5-HTP → serotonin.

Special enzymes: TPH (tryptophan hydroxylase), DDC (decarboxylase).

Cofactor: BH₄ (tetrahydrobiopterin)

🟢 Example: Serotonin regulates mood, sleep, and appetite.

5️⃣ Dopaminergic Neurons (light blue)

Main transmitter: Dopamine.

Source: Made from tyrosine → L-DOPA → dopamine.
Special enzyme: TH (tyrosine hydroxylase), DDC.

Cofactor: BH₄.

🟢 Example: Dopamine drives motivation, reward, and movement.

6️⃣ Noradrenergic / Octopaminergic Neurons (red)

Main transmitter: Norepinephrine (mammals) or Octopamine (in invertebrates).

Source: Derived from tyrosine/tyramine.

Special enzyme: TBH (tyramine β-hydroxylase).
Cofactor: BH₄.

🟢 Example: Linked to arousal and “fight or flight.”

7️⃣ Tyraminergic Neurons (orange-brown)

Main transmitter: Tyramine.

Source: Made from tyrosine → tyramine.

Special enzyme: TDC (tyrosine decarboxylase).
🟢 Example: Acts as a trace amine, modulating dopamine and serotonin systems.

Supporting Pathways (Panels B & C):
Acetyl-CoA production (B): from the citric acid cycle, provides building blocks for acetylcholine.

BH₄ synthesis (C): a critical cofactor for making serotonin, dopamine, and norepinephrine.

Each neurotransmitter system has its own “assembly line”: specific precursors, enzymes, and cofactors. Together, they form the brain’s chemical language — acetylcholine for movement and attention, glutamate and GABA for balance, and monoamines (serotonin, dopamine, norepinephrine) for mood, reward, and arousal.

28/09/2025

Hot off the press 🔥

The Broken Wing Sign🦅: A New Clinical Test to Detect Gluteus Medius Pathology with and without Fatty Infiltration

🦵 Gluteus medius pathology, including tendon tears and fatty degeneration, is a major cause of lateral hip pain, limp, and functional impairment (Kenanidis et al., 2020; Pianka et al., 2021). These lesions are common in patients with hip osteoarthritis and after total hip arthroplasty (THA) and can significantly impact surgical outcomes (Whiteside & Roy, 2019; Howell et al., 2001; Bunker et al., 1997). While magnetic resonance imaging (MRI) remains the gold standard for evaluating tendon integrity and fatty infiltration (Bogunovic et al., 2015; Engelken et al., 2014), it is not always readily available preoperatively. Clinical tests such as the Trendelenburg sign and resisted abduction are widely used, but they suffer from limited sensitivity and practical constraints (Bird et al., 2001; Ortiz-Declet et al., 2019). Therefore, novel physical examination maneuvers that correlate with MRI and intraoperative findings are needed for early and accurate detection of hip abductor insufficiency.

📘 Sierra et al. (2025, https://pubmed.ncbi.nlm.nih.gov/40938961/) introduced the “broken wing sign”, a new clinical test designed to detect gluteus medius tears and muscle atrophy. In a prospective study of 59 patients (75 hips; mean age 69.5 years), the maneuver was performed in a prone position with the knee flexed at 90°, requiring active hip extension (figure below). A positive sign was defined as ≥10° of compensatory external rotation, with ≥30° considered “highly positive.”

🩻 MRI and intraoperative findings served as reference standards.

✅ The test demonstrated strong diagnostic performance, with 81.8% sensitivity, 80.0% specificity, and a diagnostic odds ratio of 17.8 for detecting any tear.

✅ For massive tears, the negative predictive value reached 96.1%.

✅A ≥30° threshold yielded 100% specificity and positive predictive value for tendon tears.

✅The degree of external rotation correlated with fatty infiltration severity, showing 88% sensitivity for Goutallier grade ≥3 and 100% sensitivity for grade 4.

💡 Compared to the Trendelenburg sign, which was often unfeasible due to pain or poor balance, the broken wing sign was easier to perform and maintained comparable diagnostic accuracy. The authors conclude that this maneuver provides a reliable, accessible, and clinically valuable tool to guide MRI utilization, preoperative planning, and management of abductor pathology.

📸 Fig. 1-A The patient is positioned prone on the examination table with the right knee flexed to 90°. While actively extending the right hip, the leg is lifted straight upward, maintaining the thigh in neutral rotation. No excessive internal or external rotation is observed, indicating a negative broken wing sign (normal finding).

📸 Fig. 1-B In the same position, weakness of the contralateral gluteus medius allows the hip to drift into external rotation, causing the foot to move inward toward the midline. This compensatory motion indicates a positive broken wing sign.



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📚 References

• Bird, P. A., Oakley, S. P., Shnier, R., & Kirkham, B. W. (2001). Prospective evaluation of magnetic resonance imaging and physical examination findings in patients with greater trochanteric pain syndrome. Arthritis & Rheumatism, 44(9), 2138–2145.

• Bogunovic, L., Lee, S. X., Haro, M. S., Frank, J. M., Mather, R. C. III, Bush-Joseph, C. A., & Nho, S. J. (2015). Application of the Goutallier/Fuchs rotator cuff classification to the evaluation of hip abductor tendon tears and clinical correlation with outcome after repair. Arthroscopy, 31(11), 2145–2151.

• Bunker, T. D., Esler, C. N., & Leach, W. J. (1997). Rotator-cuff tear of the hip. Journal of Bone and Joint Surgery (Br), 79(4), 618–620.

• Engelken, F., Wassilew, G. I., Köhlitz, T., Brockhaus, S., Hamm, B., Perka, C., & Diederichs, G. (2014). Assessment of fatty degeneration of the gluteal muscles in patients with THA using MRI. Journal of Arthroplasty, 29(1), 149–153.

• Howell, G. E., Biggs, R. E., & Bourne, R. B. (2001). Prevalence of abductor mechanism tears of the hips in patients with osteoarthritis. Journal of Arthroplasty, 16(1), 121–123.

• Kenanidis, E., Kyriakopoulos, G., Kaila, R., & Christofilopoulos, P. (2020). Lesions of the abductors in the hip. EFORT Open Reviews, 5(8), 464–476.

• Ortiz-Declet, V., Chen, A. W., Maldonado, D. R., Yuen, L. C., Mu, B., & Domb, B. G. (2019). Diagnostic accuracy of a new clinical test (resisted internal rotation) for detection of gluteus medius tears. Journal of Hip Preservation Surgery, 6(4), 398–405.

• Pianka, M. A., Serino, J., DeFroda, S. F., & Bodendorfer, B. M. (2021). Greater trochanteric pain syndrome: Evaluation and management of a wide spectrum of pathology. SAGE Open Medicine, 9, 20503121211022582.

• Sierra, R. J., Guarin Perez, S. F., Restrepo, D. J., Howe, B. M., & Tai, T.-W. (2025). The broken wing sign: A new clinical test to detect gluteus medius pathology with and without fatty infiltration. Journal of Bone and Joint Surgery (Am), 00, 1–6. https://doi.org/10.2106/JBJS.25.00427

• Whiteside, L. A., & Roy, M. E. (2019). Incidence and treatment of abductor deficiency during total hip arthroplasty using the posterior approach. Bone & Joint Journal, 101-B(6_Supple_B), 116–122.

25/09/2025

🦴✨ Stages of Bone Fracture Healing ✨🦴

After a bone fracture, an inflammatory response occurs that lasts for 2 weeks 🔥. This phase starts an intricate network of proinflammatory signals and growth factors. Polymorphonucleate (PMN) cells and macrophages 🧪 are recruited to endocyte microdebris and micro-organisms derived from the fracture. The damage to the blood vessels results in edema 💧.

📆 After 2–3 weeks from the fracture, endochondral bone formation occurs. During this process, the mesenchymal stem cells (MSCs) are recruited to the injured site and begin to differentiate into chondroblasts (chondrogenesis) 🧬, which proliferate into chondrocytes, resulting in soft calluses 🩹. Chondrocytes synthesize and secrete the cartilage matrix, containing type II collagen and proteoglycans.

🗓️ Between the 3rd and 6th week, the cartilage undergoes hypertrophy and mineralization in a spatially organized way. New MSCs are recruited which differentiate into osteoblasts, leading to the formation of interwoven bone (hard callus) 🪨. Mineralized bone formation is induced by the signaling of factors such as Bone Morphogenetic Proteins (BMP) and TGF-β2/β3 in the cartilaginous callus.

⏳ The last phase of bone remodeling begins 8 weeks after fracture and can last up to 2 years 🕰️. Communication between osteoclasts and osteoblasts mediates the replacement of braided bone with lamellar bone 🧱 through two key activities:

🔹 Removal of bone (resorption) by osteoclasts
🔹 Formation of bone matrix by osteoblasts

💪🦴 Our bones are amazing healers!

Illustration: https://cellregeneration.springeropen.com/articles/10.1186/s13619-025-00225-1

22/09/2025

21/09/2025

Just published 🔥

📖 Toward a Better Understanding of Hip Adductor Function: Internal Rotation Capability Revealed by Anatomical and MRI Evaluation

▶️ The hip adductor group plays a central role in hip adduction and contributes to flexion and extension depending on joint angle (Dostal et al., 1986; Neumann, 2010). However, its role in hip rotation remains disputed, with anatomical texts providing inconsistent accounts of internal versus external rotation capabilities (Saladin, 2010; Standring, 2021; Gilroy et al., 2016). Functional studies have also yielded conflicting results (Leighton, 2006).

▶️ Internal hip rotation is crucial for gait efficiency and pelvic rotation during walking (Murray et al., 1964) and is essential in sports activities such as kicking and cutting. While the adductor magnus has been well described (Takizawa et al., 2014; Benn et al., 2018), little is known about the rotational function of the pectineus, adductor longus, and brevis. Cadaveric studies have explored muscle moment arms (Delp et al., 1999; Gottschalk et al., 1989), but translation to living humans requires imaging-based methods. MRI T2 mapping has emerged as a non-invasive index of muscle activity, showing strong correlations with exercise intensity and electromyography (Fisher et al., 1990; Yue et al., 1994; Adams et al., 1992).

📘 Hirano et al. (2025) addressed this gap by combining anatomical evaluation of cadavers with MRI-based analysis in healthy participants to clarify the rotational role of the hip adductor group. (https://www.mdpi.com/2411-5142/10/3/354)

🧪 Methods

☠️ Cadaveric study: Six fixed specimens (8 limbs, aged 61–96 years) were analyzed to observe muscle orientation relative to the femoral neck and gluteus minimus, and muscle length changes during passive hip internal and external rotation.

🩻 MRI study: Eight healthy adults (mean age 29.1 years) performed hip internal (forward step) and external (backward step) rotation exercises under 10% body weight load. Pre- and post-exercise T2 values of the pectineus, adductor longus, and brevis were measured. Paired t-tests, effect size (Hedges’ g), and intraclass correlation coefficients (ICC) were used for analysis.

📊 Results

✅ Anatomical observations: The pectineus, adductor longus, and brevis were oriented nearly parallel to the femoral neck and gluteus minimus. Internal rotation shortened, while external rotation lengthened, these muscles.

✅ MRI findings: T2 values significantly increased after internal but not external rotation. Percent change was higher for internal versus external rotation:

👉 Pectineus: 6.38% vs. 1.35%

👉 Adductor longus/brevis: 4.84% vs. 1.31%

👉 Effect sizes exceeded 0.8 with high power, and ICCs demonstrated excellent reliability.

💡 Discussion

▶️ The findings indicate that the pectineus, adductor longus, and brevis function as hip internal rotators in addition to their stabilizing role in the coronal plane. These muscles appear to act in synergy with the gluteus minimus and posterior gluteus medius to stabilize and internally rotate the hip, particularly in standing, closed-chain conditions.

▶️ Clinically, this expands understanding of gait biomechanics and supports the inclusion of adductor training in rehabilitation programs targeting gait efficiency, pelvic control, and athletic performance. Limitations include small sample sizes and reliance on elderly cadavers, suggesting the need for broader, biomechanically integrated studies.

🏃 Conclusions

▶️ The adductor muscle group contributes significantly to hip internal rotation and frontal plane stability. By integrating anatomical and MRI-based evidence, this study refines the functional role of the adductors, providing clinically relevant insights for both rehabilitation and sports science.

📚 References

Adams, G.R., Duvoisin, M.R., & Dudley, G.A. (1992). Magnetic resonance imaging and electromyography as indexes of muscle function. J. Appl. Physiol., 73, 1578–1583.

Benn, M.L., Pizzari, T., Rath, L., Tucker, K., & Semciw, A.I. (2018). Adductor magnus: An EMG investigation into proximal and distal portions and direction specific action. Clin. Anat., 31, 535–543.

Delp, S.L., Hess, W.E., Hungerford, D.S., & Jones, L.C. (1999). Variation of rotation moment arms with hip flexion. J. Biomech., 32, 493–501.

Dostal, W.F., Soderberg, G.L., & Andrews, J.G. (1986). Actions of hip muscles. Phys. Ther., 66, 351–359.

Fisher, M.J., Meyer, R.A., Adams, G.R., Foley, J.M., & Potchen, E.J. (1990). Direct relationship between proton T2 and exercise intensity in skeletal muscle MR images. Invest. Radiol., 25, 480–485.

Gilroy, A.M., MacPherson, B.R., Schuenke, M., Schulte, E., & Schumacher, U. (2016). Atlas of Anatomy (3rd ed.). Thieme Medical Publishers.

Gottschalk, F., Kourosh, S., & Leveau, B. (1989). The functional anatomy of tensor fasciae latae and gluteus medius and minimus. J. Anat., 166, 179–189.

Hirano, K., Kinosh*ta, K., Senoo, A., & Watanabe, M. (2025). Toward a better understanding of hip adductor function: Internal rotation capability revealed by anatomical and MRI evaluation. J. Funct. Morphol. Kinesiol., 10, 354.

Leighton, R.D. (2006). A functional model to describe the action of the adductor muscles at the hip in the transverse plane. Physiother. Theory Pract., 22, 251–262.

Murray, M.P., Drought, A.B., & Kory, R.C. (1964). Walking patterns of normal men. J. Bone Joint Surg. Am., 46, 335–360.

Neumann, D.A. (2010). Kinesiology of the hip: A focus on muscular actions. J. Orthop. Sports Phys. Ther., 40, 82–94.

Saladin, K. (2010). Human Anatomy (3rd ed.). McGraw-Hill.

Standring, S. (Ed.). (2021). Gray’s Anatomy: The Anatomical Basis of Clinical Practice (42nd ed.). Elsevier.

Takizawa, M., Suzuki, D., Ito, H., Fujimiya, M., & Uchiyama, E. (2014). Why adductor magnus muscle is large: The function based on muscle morphology in cadavers. Scand. J. Med. Sci. Sports, 24, 197–203.

Yue, G., Alexander, A.L., Laidlaw, D.H., Gmitro, A.F., Unger, E.C., & Enoka, R.M. (1994). Sensitivity of muscle proton spin-spin relaxation time as an index of muscle activation. J. Appl. Physiol., 77, 84–92.


📸 Illustration: PE pectineus, GR gracilis, AL adductor longus, AB adductor brevis, AM adductor magnus, https://link.springer.com/book/10.1007/978-3-319-09480-9

15/09/2025

Anatomy and biomechanics of the posterior cruciate ligament (PCL) and related structures 🦵

▶️ The posterior cruciate ligament (PCL) is an intra-articular, extrasynovial structure with a mean midsubstance length of approximately 36–38 mm and a cross-sectional area between 40 and 60 mm², making it larger and stronger than the anterior cruciate ligament (ACL) [4,10]. Morphologically, the PCL is flat-oval rather than round and exhibits a twisted fiber orientation [4].

▶️ Anatomically, the ligament is divided into two distinct bundles: the anterolateral bundle (ALB) and the posteromedial bundle (PMB). The ALB is typically larger and stronger, whereas the PMB is smaller and more variable in shape and insertion [4,10]. Although earlier work emphasized a reciprocal function between the bundles, more recent investigations have demonstrated codominance of the ALB and PMB, with both contributing substantially to restraint throughout the entire range of knee flexion [2,5,6].

▶️ The femoral footprint is a half-moon–shaped area on the medial femoral condyle, with a surface area of approximately 190–230 mm² [3,4]. On the tibial side, the ligament inserts on the posterior intercondylar fossa, adjacent to the posterior horns of the menisci, with an attachment area of 160–220 mm² [3]. Neighboring structures include the meniscofemoral ligaments of Humphrey (anterior) and Wrisberg (posterior), which are present in over 90% of knees and insert near the PMB region, thereby supporting posterior stability [3].

▶️ From a structural perspective, tensile testing has confirmed that the PCL exhibits greater strength and stiffness than the ACL [4,10]. Both bundles undergo angle-dependent length and strain changes during flexion, reflecting the complex geometry of the ligament. The ALB typically experiences greater elongation and loading in mid-flexion, while the PMB is more engaged in extension and deep flexion [2,5].

▶️ Functionally, the PCL is the primary restraint against posterior tibial translation (PTT) across the entire arc of motion [4,6,7]. The codominant behavior of the ALB and PMB ensures that posterior stability is preserved at multiple flexion angles [2,5,6]. In addition, the ligament provides a secondary restraint against internal and external tibial rotation, especially in flexion angles greater than 90° [6,9].

▶️ The PCL interacts closely with peripheral stabilizers. The posterolateral corner (PLC), comprising the lateral collateral ligament, popliteus tendon, and popliteofibular ligament, functions synergistically with the PCL to resist varus stress and external rotation. Injury to the PLC or posteromedial corner (PMC) increases forces borne by the PCL or its grafts and represents a major risk factor for failure if not addressed during reconstruction [8].
Partial PCL injuries involving only one bundle may produce subtle increases in laxity that are difficult to detect clinically, whereas complete ruptures result in significant posterior translation and excessive rotational instability [9].

📸Illustration: Schematic illustration of the anatomy of the posterior cruciate and the meniscofemoral ligaments. a Right knee from an antero-lateral view. b Right knee from a posterior view. ACL anterior cruciate ligament; ALB anterolateral bundle; aMFL anterior meniscofemoral ligament; LCL lateral collateral ligament; LM lateral meniscus; MCL medial collateral ligament; MM medial meniscus; PFL popliteofibular ligament; PMB posteromedial bundle; pMFL posterior meniscofemoral ligament; PT popliteus tendon, https://link.springer.com/article/10.1007/s00167-020-06357-y

📚 References

1. Winkler PW, Zsidai B, Wagala NN, Hughes JD, Horvath A, Hamrin Senorski E, Samuelsson K, Musahl V. Evolving evidence in the treatment of primary and recurrent posterior cruciate ligament injuries, part 1: anatomy, biomechanics and diagnostics. Knee Surg Sports Traumatol Arthrosc. 2021;29:672–681.

2. Ahmad CS, Cohen ZA, Levine WN, Gardner TR, Ateshian GA, Mow VC. Codominance of the individual posterior cruciate ligament bundles: an analysis of bundle lengths and orientation. Am J Sports Med. 2003;31:221–225.

3. Amis AA, Gupte CM, Bull AM, Edwards A. Anatomy of the posterior cruciate ligament and the meniscofemoral ligaments. Knee Surg Sports Traumatol Arthrosc. 2006;14:257–263.

4. Harner CD, Xerogeanes JW, Livesay GA, et al. The human posterior cruciate ligament complex: an interdisciplinary study. Ligament morphology and biomechanical evaluation. Am J Sports Med. 1995;23:736–745.

5. Papannagari R, DeFrate LE, Nha KW, et al. Function of posterior cruciate ligament bundles during in vivo knee flexion. Am J Sports Med. 2007;35:1507–1512.

6. Kennedy NI, Wijdicks CA, Goldsmith MT, et al. Kinematic analysis of the posterior cruciate ligament, part 1: the individual and collective function of the anterolateral and posteromedial bundles. Am J Sports Med. 2013;41:2828–2838.

7. Wijdicks CA, Kennedy NI, Goldsmith MT, et al. Kinematic analysis of the posterior cruciate ligament, part 2: a comparison of anatomic single- versus double-bundle reconstruction. Am J Sports Med. 2013;41:2839–2848.

8. Harner CD, Vogrin TM, Höher J, Ma CB, Woo SL. Biomechanical analysis of a posterior cruciate ligament reconstruction. Deficiency of the posterolateral structures as a cause of graft failure. Am J Sports Med. 2000;28:32–39.

9. Markolf KL, Feeley BT, Tejwani SG, Martin DE, McAllister DR. Changes in knee laxity and ligament force after sectioning the posteromedial bundle of the posterior cruciate ligament. Arthroscopy. 2006;22:1100–1106.

10. Race A, Amis AA. The mechanical properties of the two bundles of the human posterior cruciate ligament. J Biomech. 1994;27:13–24.