Lower limb soft tissue injuries

by Kirsty Berry, Shaun De Villiers & Marc Nortje

---

Introduction

Ligament, tendon and muscle injuries of the hip, knee and ankle are common conditions seen in emergency departments and general practice. The majority of these injuries can be treated with conservative management. It is essential to identify injuries that should be referred to an orthopaedic surgeon for possible surgical intervention or further work-up.

Groin injuries

Also known as an adductor strain.

Clincial Findings

History

Most often young athletes complain of groin pain following an injury while playing sport (most often running). It is more common in males than in females.

Examination

• Tenderness in the groin.
• Antalgic gait.
• Pain on resisted adduction of the hip, passive end of range abduction of the hip (adductors stretched), or both.

Additional injuries to note

It is essential to rule out non-orthopaedic causes such as inguinal hernias.

Special investigations

Imaging

• X-rays are normal.
• MRI – show changes in the adductor (oedema or tear); most often not indicated.

Management

Non-Surgical

• RIC(E):
• Rest
• ICE
• Compression
• Physiotherapy for rehabilitation and return to activity.

Surgical

Rarely indicated.

Ligament and meniscal injuries of the knee Applied anatomy

The stability of the knee is dependent on bony anatomy, joint capsule, ligaments, menisci and surrounding muscle. The most commonly injured structures in the knee are the ligaments and menisci that can lead to ongoing pain, difficulty with daily and sporting activities and instability. The ligaments of the knee are the anterior and posterior cruciate ligaments and medial and lateral collateral ligaments. Both medial and lateral menisci contribute to stability function and articulation of the knee joint. Image 1 shows the anatomy of the ligaments and menisci.

Clincial Findings

History

• Anterior cruciate ligament – the typical history is twisting the knee with the ankle fixed and immediate swelling.
• Posterior cruciate ligament – an anterior force to the tibia in a flexed knee. Dash-board injury is the most common mechanism.
• Medial (MCL) and lateral (LCL) ligament injuries – valgus (MCL) or varus (LCL) force applied to the knee
• Multi-ligament injuries – most often seen in high-velocity motor vehicle accidents or patients with a high BMI and low-velocity injuries.
• Meniscal injuries – the typical history is twisting motion on the fixed ankle with delayed swelling.

Examination

• Look
• Swelling is typical of all injuries around the knee.
• Feel
• Joint effusion may be seen with all injuries and can be assessed with the patella tap test. Tenderness over the MCL or LCL collateral may indicate an injury in this area. Anterior lateral or medial pain on palpation may point to lateral or medial meniscal injuries, respectively.
• Move
• Range of motion of the knee may be limited (normal 0–130).
• Anterior and posterior draw test – ACL and PCL
• Lachmann and reverse Lachmann – ACL and PCL
• Varus and valgus stress tests – lateral and medial collateral ligaments, respectively
• McMurray’s meniscal injuries

Additional injuries to note

• May be associated with vascular injuries (especially in multi-ligament injuries); vascular assessment is essential.
• High suspicion of reduced knee dislocation in patients with multi-ligament knee dislocations.
• Poly-trauma patients must be assessed closely in the case of a swollen knee and normal X-rays

Special investigations

Imaging

• Plain film X-rays may be normal.
• Horizontal beam lateral (HBL) view may show an effusion (lipohaemarthrosis).
• Stress views are useful in diagnosing ligament injuries (compare to the contralateral side).
• Soft tissue swelling can be seen on plain film X-rays.
• An MRI is the gold standard for assessing soft tissue injuries.

Management

Non-surgical

• Rest
• Ice
• Compression
• Elevation
• Crutches with partial weight-bearing for pain management
• Analgesia (including NSAIDs where indicated)

Surgical

• Failure of conservative management in the non-athlete, with ongoing pain and instability after six weeks.
• Multi-ligament knee injuries.
• ACL and meniscal injuries.
• Surgery includes arthroscopic or open repair or reconstruction of ligaments; debridement, repair or replacement of menisci.

Achilles’ tendon rupture

Applied anatomy

The Achilles tendon is the confluence of the soleus and gastrocnemius muscles of the posterior compartment of the leg. It inserts onto the posterior aspect of the calcaneus tuberosity. Its primary function is plantar flexion of the ankle joint.

Clinical findings

History

Most often, a low-velocity injury. The foot is either forced into extreme plantarflexion or dorsiflexion from a maximal plantarflexed position. A popping sound may be heard at the time of injury. The patient may have pain in the heel or calf and difficulty walking. The so-called ‘weekend warrior’ is vulnerable to this type of injury. The use of fluoroquinolones and steroid injections around the ankle has been associated with Achilles’ tendon rupture.

Examination

• Tenderness and ecchymosis around or proximal to the insertion of the tendon.
• A gap in the tendon on palpation.
• Inability to actively plantarflex.
• Thompson test – pathognomonic.

Differential diagnosis

• Ankle sprain
• Ankle fractures
• Calcaneus fractures

Special investigations

Imaging

• X-rays are normal.
• Ultra-sound – confirm the clinical diagnosis; determine the size of the gap and differentiate between partial and complete tears.
• MRI – helpful if the clinical diagnosis is unclear or for surgical planning in chronic tears.

Management

All patients with Achilles’ tendon rupture should be referred to an orthopaedic surgeon.

Non-surgical

Serial casting progressing from plantar flexion to neutral every two weeks for 6–12 weeks has shown good outcomes in the low demand patient with acute tendon rupture.

Surgical

• An open or percutaneous repair can be considered for closed injuries.
• Open injuries with direct laceration rather than tear should be repaired primarily.
• Tendon reconstruction and transfers are surgical options in chronic tears.

Ankle sprain

Applied anatomy

Ankle sprains involve injury to the lateral ligament structures of the ankle, specifically the anterior talofibular (ATFL) and the calcaneofibular ligaments (CFL).

Clinical findings

History

Inversion on a plantarflexed foot. The patient often reports ‘twist of the ankle’.

Examination

• Oedema and ecchymosis around the lateral aspect of the ankle
• Tenderness over the lateral ankle (both lateral malleolus and talus).
• Inability to weight-bear.
• Anterior draw test for the ankle may be positive.
• Talar tilt test – inversion (especially end of range) causes pain.

Additional injuries to note

• Fractures of the ankle (lateral malleolus) and tarsal bones (especially talus and calcaneus) must be ruled out.
• Syndesmosis injuries can present as high ankle sprains (positive squeeze test).

Special investigations

Imaging

• X-rays – normal bony anatomy; soft tissue swelling may be evident.
• MRI – only indicated in chronic injuries or where the diagnosis is unclear.

Management

Non-surgical

• The majority of injuries improve with non-surgical intervention. The mainstay of treatment is ‘RICE’:
• Rest
• Ice
• Compression
• Elevation
• Non-weight or partial weight-bearing for pain relief.
• Physiotherapy

Surgical

• Indicated where conservative measures have failed.
• Arthroscopy of the ankle for diagnosis and debridement of the joint.
• Repair or reconstruction of the ATFL or tendon rerouting.