When Achilles Tendonitis Is Not Caused By A Tight Achilles

By Babak Baravarian, DPM

A patient comes into the office with an aching sensation in the posterior aspect of the right leg. He notes the pain has been increasing in the past two to three months and has gotten worse since he began to exercise. Specifically, in the past three weeks, the patient says he has had tightness in the Achilles tendon region. During that specific time period, the patient notes that he began a walking program on a slight hill by his house. He notes the hill provides a slight exertion that has been excellent for his stamina. The patient says he has only had the pain after a long climb and when he works out more than two times per week. He has tried over-the-counter orthotics, physical therapy for Achilles tendonitis as per his internist and a course of non-steroidal antiinflammatory medication as well. What Does The Examination Reveal? The patient is a healthy 24-year-old male who is slim and muscular in nature. Upon doing a clinical examination, we found that the patient has excellent muscle strength and only notes pain in the watershed region or distal midsubstance of the Achilles tendon. We did note callus formation of the forefoot, plantar to metatarsal heads one through four. The fifth metatarsal head is slightly callused. While there is no pain in the forefoot, the patient does have mild extensor tightness of the toes with mild hammering of all the toes. The hammering is flexible and reduces with patient ambulation and plantar pressure on the metatarsal heads. Dorsiflexion of the foot causes some extensor use. The patient’s rearfoot is well positioned with adequate motion of calcaneus and ankle. There is an equinus of the ankle with full dorsiflexion, which is soft in nature. There is no alteration in the equinus with the knee bent or straight. Upon doing a lateral inspection of the foot, we noted a cavus foot, which does not reduce with dorsal forefoot pressure. The patient has tightness of the plantar foot musculature and the plantar fascia. On a lateral plane, the forefoot lays below the level of the rearfoot with increased plantar position of the first metatarsal in comparison to the lateral metatarsals. Radiographs reveal a cavus foot with an increase in the calcaneal inclination angle and a plantarflexed forefoot position. The high point of the foot is in the midfoot at the region of the naviculocuneiform joint. Gait analysis reveals a normal gait pattern with a slight lateral heel position and an early heel off with ambulation. The patient inverts when standing and stays in a supinated position during the entire gait cycle. When we question this patient further as to walking patterns, he reveals that he has had mild midfoot pain and slight anterior ankle pain with ambulation. These problems have also been increasing in severity in the past three months. What Is The Diagnosis? 1. Primary Achilles tendonitis secondary to Achilles equinus 2. Gait changes due to arthritis of the foot 3. A supinated gait pattern causing Achilles tendonitis 4. A cavus deformity causing Achilles tendonitis. The correct answer is a cavus deformity causing Achilles tendonitis. However, this is a very simplistic answer to a very difficult problem. In order to provide effective treatment, one has to determine if the patient has a global cavus, a forefoot cavus, a rearfoot cavus or a combination cavus. Diagnostic Answers In order to understand cavus deformity, you need to consider the foot as a tripod. If the first metatarsal sits below the level of the lateral metatarsals, the foot or tripod will tilt laterally. If the heel is in varus position, the foot or tripod tilts laterally. If the entire forefoot sits below the level of the heel, the foot may not tilt medially or laterally, but may require additional dorsiflexion to get to a rectus position. This additional dorsiflexion may place a strain on the posterior ankle tendons and cause impingement on the anterior ankle region. There may also be strain on the high point of the foot with a global forefoot cavus. The best test of cavus feet is to perform a Coleman block test. Do this by placing the forefoot on the block and allow the heel and first metatarsal to hang off the block. If the heel position goes from varus without use of the block to rectus with use of the block, the heel varus is secondary to the first metatarsal being plantarflexed and is not due to the actual heel position. If there is no change, then there is a possible heel varus and a plantarflexed first metatarsal. In our patient, the block test reveals a rectus heel position with the heel and first metatarsal placed off the block. This shows us the heel position is not a problem and the varus heel is secondary to the plantarflexed first metatarsal. However, our lateral inspection reveals that the forefoot is sitting below the level of the rearfoot, there is callus on all the metatarsal heads and the first metatarsal is sitting below the level of the lateral metatarsals. Should You Consider Orthotic Management? Orthotics can be helpful in treating many cavus deformities. Cases of plantarflexed first metatarsals do very well with orthotic accommodation and decreased plantar pressure on the medial aspect of the forefoot. However, this particular case will not benefit greatly from orthotics. When you are dealing with a global plantarflexed position, the stress on the midfoot, anterior ankle and Achilles region is caused by a lack of enough dorsiflexion to bring the forefoot to a rectus level. This is exaggerated and exacerbated with hill climbing. We gave our patient a course of physical therapy and told him not to climb any hills. His pain resolved to a small degree yet he felt continued aching of the Achilles tendon and anterior ankle region. He understood this problem would not get better with time and requested an opinion as to surgical reconstruction options. Choosing A Surgical Option Cavus deformity correction is a very complex problem to treat. You must make sure there are no neurological symptoms that have caused muscle or tendon weakness. Treatment of the deformity is aimed at balancing the foot into three equal points of weight distribution, a tripod. The three points are the heel, medial forefoot and lateral forefoot. The second point is to place the forefoot and rearfoot at the same level on a lateral view. In our patient, dorsiflexion of the first metatarsal alone will not relieve the problem. A calcaneal osteotomy is also not needed as the block test revealed a rectus heel position. The surgery of choice in this case is a Steindler stripping and a dorsiflexory procedure of the forefoot. One may do this at the Lisfranc’s joint with an arthrodesis. However, it is best performed at the midfoot level through the naviculocuneiform and cuboid region as described by Cole. While the Cole midfoot osteotomy is a difficult procedure, it is excellent for the treatment of global forefoot equinus. It is also important to consider the fact that there may be some degeneration of the Achilles tendon and synovitis or scarring of the anterior ankle. This may require treatment at the time of surgical reconstruction. However, it is usually better to treat this after the reconstruction as the reconstruction will decrease pressure on these regions and will relieve some of the symptoms. One should perform the Cole osteotomy through a medial incision centered over the naviculocuneiform joint and a second lateral incision centered over the cuboid. Connecting the incisions on the dorsal aspect protects the dorsal neurovascular structures and tendon structures. Place wires from medial to lateral for osteotomy positioning. Proceed to make the osteotomy with a plantar apex removing a wedge of bone. The wedge should be slightly larger on the medial than the lateral aspect in order to dorsiflex the medial column slightly more than the lateral column. You would achieve fixation through pin placement on the medial and lateral columns. Pin fixation is simple and easy to remove following healing. Instruct the patient to avoid placing any weight on the foot for six to 10 weeks. This should be followed by guarded weightbearing in a walking boot and physical therapy for three weeks. Although this procedure is challenging and not often necessary, it is an excellent procedure that can provide sound outcomes for properly selected patients. Dr. Baravarian is the Chief of Podiatric Surgery at Santa Monica/UCLA Medical Center and is the Co-Director of the Foot and Ankle Institute of Santa Monica in Santa Monica, Calif.

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